CAM Practices Paper

CHAPTER 25 NUTRITION AND HYDRATION

MARC S. MICOZZI

People eat food, not nutrients. When we rummage through the refrigerator for a snack or cruise the supermarket aisles trying to decide what to fix for dinner, our choices are much more likely to reflect cultural, social, and family patterns than to be based on the federal government's food pyramid and recommended daily allowances.

Food has powerful symbolic meaning and has played a key role in our religious and social rituals for thousands of years. From birthday cake to the bitter herbs of the Passover seder to Thanksgiving turkey to communion wafers, food helps form our social bonds, express our spirituality, and define who we are. Rituals remain powerful even when we no longer recall their origins. For example, Christians worldwide celebrate Easter by eating colored eggs, although few could explain the connection between hard-boiled eggs and Jesus’ resurrection.

Substances can have radically different meanings for different groups. For Muslims, Christian Scientists, and members of Alcoholics Anonymous, wine is strictly “taboo,” whereas for Catholics, wine is part of a sacrament that is by definition “an outward sign instituted by Christ to give grace.” Individuals also bring very different perspectives to the table. For some vegetarians, chicken soup represents cruelty to animals, whereas for many other people, it recalls Mom's tender care during childhood illnesses.

An intellectual understanding of what constitutes good nutrition is no match for the powerful psychological, social, and spiritual forces that have been shaping human eating habits since the Stone Age.

EATING HABITS OF EARLY HUMANS

Humans are omnivores. We can eat almost everything found in nature, and with a few exceptions (e.g., wood, grass), we can extract nutrition from whatever we consume. For hundreds of thousands of years, our early ancestors roamed the forests and plains as hunter-gatherers. The hunters brought home very lean meat; wild game has only 4% to 6% body fat versus the 40% to 60% body fat found in modern domesticated animals. The gatherers collected plants that were high in fiber and complex carbohydrates and provided many necessary vitamins. These early humans obtained calcium from animal bones and other minerals from the dirt that inevitably clung to wild plants and game.

Life was a constant struggle to obtain enough fat and calories, and our ancestors developed a decided preference for foods that tasted rich in these needed nutrients. In the small, hunter-gatherer tribes, food was often allocated on the basis of social status, gender, and age, which provided it with significance beyond the satisfaction of hunger. When agriculture was developed 10,500 years ago, diets became more stable. Seasonal crops led to seasonal feasts, which added another layer of cultural meaning to food consumption.

Although even the earliest farmers sought to improve their crops genetically—for example, selecting and sowing the seeds of wheat that had stronger stalks and quicker, more uniform germination—the quality of food did not change much. Humans learned to use yeast (made from microbes, which had been present on the planet for millions of years) to produce bread, beer, and wine; other microbes were used to make cheese and yogurt. These microbes made certain plants and dairy products easier (and more enjoyable) to consume and digest, but humans were still eating the diet for which their digestive system and metabolism were designed: low in fat and high in protein, complex carbohydrates, and fiber, with no refined sugar. Everything in the human diet remained completely natural—until modern times.

MODERN ERA: FOOLING MOTHER NATURE

Fast-forwarding to the twentieth century, we find a very different picture of food production and consumption. Early in the century, advances in biochemistry allowed scientists to isolate some of the active ingredients in food. In 1928, for example, it was discovered that limes, the British Navy's traditional method of preventing scurvy, worked by providing sailors with vitamin C. Unfortunately, although vitamin C supplements proved easier to store and dispense, they did not provide the full benefits of the fruit. Later research disclosed that lime pulp contains bioflavonoids, which are necessary for absorbing and processing vitamin C. Bioflavonoids also help maintain collagen and capillary walls and protect against infection and cancer. Scientists were discovering that replacing natural products with artificial ones did not always improve on the original.

This finding, however, did not stop scientists from trying to improve on nature. Currently, modern technology and agribusiness have “improved” crops by covering them with artificial chemicals, including pesticides, fungicides, ripening agents, and fumigants, all of which make them more efficient to grow, ship, and store. Genetic engineering has changed the biological structure of many plants in ways not yet fully understood. Some plants are irradiated (flooded with “harmless” radiation) to lengthen their shelf life. Animals destined for the table are dosed with antibiotics to prevent disease and with hormones to make them fat and juicy.

Once vegetables, fruit, milk, meat, and eggs leave the farm, they are often “processed” into “food products,” such as canned soup and frozen dinners. Processed foods are generally high in fat, salt, and sugar; are lower in nutrients than fresh foods; and contain a host of chemicals to boost flavor, color, texture, and shelf life. Consider the following:

• Pounds of sugar the average American consumed per year in the nineteenth century: less than 10

• Pounds of sugar the average American consumes per year today: 150

Among the many artificial substances used in processed foods are such synthetic sweeteners as aspartame, silicon dioxide, phenylalanine, tribasic calcium phosphate, benzosulfimide, and calcium silicate. The effects of all these chemicals on our bodies are not entirely known, but saccharin, the first widely used artificial sweetener, was shown to cause cancer in laboratory animals. Aspartame (NutraSweet) is now being studied for possible neurological effects. Large quantities of one of its ingredients, methanol, have been shown to cause blindness, brain swelling, and inflammation of the pancreas and heart muscle.

In addition to pseudosugars, we now have “fake fats.” Partially hydrogenated oil does not occur in nature but in the laboratory, when liquid vegetable fats are turned into solids by pumping hydrogen into them. This makes them more like animal fats in taste and feel, as well as in their harmful effects on the cardiovascular system; in fact, partially hydrogenated fats have been associated with higher cancer rates than saturated fats. Trans-fatty acids (TFAs) are formed when unsaturated fatty acids (the building blocks of fat) are deformed by certain heat or chemical treatments. These deformed fats may be toxic. TFAs in the diet may damage the regulatory machinery of the body, significantly compromising health. Despite these concerns, partially hydrogenated oils and TFAs are found in a wide range of processed foods, including almost all margarines, mass-produced breads, convenience foods, and junk foods, as well as some baby foods.

For a variety of reasons, including productivity, efficiency, convenience, profit, arrogance, and curiosity, we have found abundant ways to change the nature of our diets and the nature of the animals and plants that feed us. As a group, the U.S. population eats high on the food chain, consuming unprecedented amounts of meat, chicken, fish, dairy products, fat, salt, and sugar. We cover our food with artificial chemicals while it is grown, processed, preserved, and genetically altered in ways that have only recently been introduced on this planet. After hundreds of thousands of years of evolution, during which our bodies became perfectly adapted to drawing nutrition from the natural environment, we have suddenly introduced large quantities of new, artificial substances into our diets, hoping to improve on nature.

BOX 25-1 American Eating Habits: 1900 to 1980

Fresh fruit and vegetable consumption drops from 40% to 5% of the diet.

Sugar consumption rises 50%.

Beef consumption rises 50%.

Fat and oil consumption rises 150%.

Cheese consumption rises 400%.

Margarine consumption rises 800%.

How have these “advances” affected our health?

DISEASES OF AFFLUENCE

We have become a nation in which one third of the U.S. population is significantly overweight, and more than one quarter—24% of adult males, 27% of adult females, and 27% of children—are obese. Although this is caused by a variety of factors, ranging from genetics to the introduction of the car (reducing the necessity to move around) and television (reducing the desire to move around), a clear and direct correlation exists between food consumption and excess body weight.

Research has shown an equally clear and direct connection between excess body weight and illness, especially the leading killers in the United States: cardiovascular disease and cancer. Today, 60 million Americans have cardiovascular disease, including high blood pressure, heart disease, and stroke. This year, cardiovascular disease will kill about 1 million Americans, more than 2600 a day, or one death every 33 seconds. Another 1.2 million people will be diagnosed with cancer this year, and almost 600,000 will die of it. Thousands more will suffer from other diseases related to diet: diabetes, gallbladder disease, respiratory disease, sleep apnea, gout, osteoporosis, and a host of other conditions.

For more than a century, the U.S. Department of Agriculture (USDA) has been trying to improve our eating habits by issuing dietary recommendations. It currently spends $333.3 million per year educating the public about what we should and should not consume and in what quantities (USDA, 1997). That seems a great expenditure until we consider that America's food manufacturers spend that amount promoting snacks and nuts; their total annual advertising budget is more than $7 billion, most of which is spent promoting highly processed, packaged foods. The fast-paced American lifestyle relies on these convenience foods and on restaurant and take-out fare. We now spend 45% of our food dollars on away-from-home meals and snacks, most of which are higher in fat, salt, and sugar and lower in fiber and calcium than meals prepared at home.

According to the USDA's Healthy Eating Index, some small improvements have been made in the American diet. On a scale of 1 to 100, the average U.S. score rose from 61.5 in 1990 to 63.8 in 1995, but it still falls far short of the 80 or above that marks a good diet. Put another way, Americans are earning about a C− in healthy eating practices.

Box 25-1 lists trends in American eating habits in the twentieth century.

WHAT SHOULD WE BE EATING?

Most Americans know (but don't necessarily act on) the basic facts: a healthy diet includes lots of fresh, unprocessed fruits, vegetables, and grains; modest amounts of protein and fat; and very little white sugar and salt. The question of precisely how much of each type of food we need, however, becomes more complicated.

All food provides energy, which is measured in units called calories. Nutritionists generally recommend daily intake of 1600 calories for older adults and sedentary women; 2200 calories for children, teenage girls, active women, and sedentary men; and 2800 calories for teenage boys, active men, and very active women. Calories are taken into our bodies as carbohydrates, proteins, and fats (which are known as macronutrients, or major constituents of diet). We also require vitamins and minerals (which are effective in small amounts and thus are known as micronutrients) to process these nutrients and maintain body functions.

Nutritionists, physicians, research scientists, alternative practitioners, food manufacturers, and consumers hold differing views about what percentage of calories we should obtain from each macronutrient. People favoring a largely vegetarian, low-fat diet tend to recommend that we receive about 15% of our calories from protein, 60% from carbohydrates, and 25% from fats. Proponents of high-protein diets often advocate 30% protein, 40% carbohydrates, and 30% fats. The food pyramid, developed by the U.S. Department of Health and Human Services and USDA, suggests that we use fat “sparingly” and that our daily fare include 2 to 3 servings of dairy products; 2 to 3 servings of meat, poultry, fish, eggs, beans, and nuts; 3 to 5 servings of vegetables; 2 to 4 servings of fruit; and 6 to 11 servings of bread, cereal, rice, and pasta (Box 25-2).

Although these numbers may provide useful guidelines, they do not address one crucial factor: the quality of nutrients in each category. The food pyramid, which recommends 6 to 11 servings of grain-based foods, fails to distinguish, for example, between the empty calories of frozen waffles, which are composed primarily of white sugar and white flour, and a bowl of whole-grain cereal. It encourages us to use fats “sparingly” but advocates 2 or 3 helpings of cheese and whole milk, which contain at least 8 g of fat per serving, plus up to 3 servings of meat, which can contain up to 26 g of fat per serving. Is a Whopper (40 g of fat) part of a healthy diet? Are PopTarts (20 g of white sugar) giving us the right kind of energy to start the day?

BOX 25-2 The Changing Shape of U.S. Government Guidelines

Over the years, the U.S. Department of Agriculture has revised its dietary recommendations in response to research findings and new concepts of nutrition.

1946 to 1958: The “Basic 7” Daily Food Guide

Leafy, green, and yellow vegetables: 1 or more servings

Citrus fruit, tomatoes, raw cabbage: 1 or more servings

Potatoes and other vegetables and fruits: 2 or more servings

Milk, cheese, ice cream: children, 1 to 4 cups of milk; adults, 2 or more cups

Meat, poultry, fish, eggs, dried peas, beans: 1 to 2 servings

Bread, cereal, flour: 2 or more servings

Butter and fortified margarine: 2 tablespoons

1958 to 1979: The Four Basic Food Groups (per day, for adults)

Milk group: 2 or more cups

Meat group: 2 or more servings

Vegetable and fruit group: 4 or more servings

Bread and cereal group: 4 or more servings

1979 to 2005 The Food Pyramid (per day)

Fats, oils, sweets: use sparingly

Milk, yogurt, cheese: 3 to 5 servings

Dried beans, nuts, seeds, eggs, meat: 2 to 3 servings

Vegetables: 3 to 5 servings

Fruits: 2 to 4 servings

Bread, cereal, rice, pasta: 6 to 11 servings

2005 MyPyramid

Customized based on personal characteristics

Personal plans available at http://www.mypyramid.gov

Clearly the numbers alone do not tell the whole story. All carbohydrates are not created equal, nor does everyone need the same amount of them, or of any given nutrient. Our food needs are influenced by many factors, such as age, gender, body size, activity level, and reproductive status, and will change over time. To determine what type of diet is best for our bodies at different stages of our lives, we need some understanding of how the nutrients in food enable our bodies to function.

Carbohydrates

Carbohydrates provide large amounts of quick energy. We obtain carbohydrates from fruits, vegetables, beans, grains, and other plant materials, as well as from dairy products. Our bodies easily transform carbohydrates into glucose (blood sugar), which the body needs for fuel, and into glycogen, a form of sugar that can be stored in the liver and muscles until needed, then transformed into glucose.

There are two types of carbohydrates: simple and complex. Simple carbohydrates, or simple sugars, include white table sugar (sucrose), the sugar in fruit (fructose), and the sugar in milk (lactose). In complex carbohydrates, such as whole grains, beans, and vegetables, the sugar molecules are linked together in longer, more complicated chains.

Both types of carbohydrates become blood sugar, but the simple sugars are converted more quickly, elevating insulin levels and providing a “sugar rush” that quickly abates, often leading to feelings of tiredness. Complex carbohydrates are metabolized more slowly, providing a sustained supply of energy. One complex carbohydrate has a different role: fiber is not absorbed into the body at all but helps with digestive and bowel function. One of the disadvantages of an overprocessed, highly refined diet is that foods tend to linger in the body, which can allow carcinogens (cancer-causing substances) to be absorbed or produced by the body (see Chapter 21). Fiber in the diet has been shown to reduce constipation, which decreases the risk of colon, breast, and other cancers; it also shrinks intestinal polyps (growths), which can lead to cancers. About 25 g of fiber a day is usually sufficient and will occur naturally in a diet that includes a good supply of complex carbohydrates.

Proteins

Protein is essential for the growth, maintenance, and repair of every cell in the body and for the production of hormones, antibodies, and digestive enzymes. When we consume dietary protein, we break it down into amino acids, which are the building blocks we need to make our own proteins.

There are two types of dietary proteins: complete and incomplete. Complete proteins, which are found in meat, poultry, fish, eggs, dairy products, and soybeans, provide the full range of essential amino acids we need. Incomplete proteins, which include some but not all needed amino acids, are found in grains, beans, nuts, seeds, and leafy green vegetables. However, incomplete proteins can be combined to provide the full range of amino acids our bodies require. For example, brown rice served with beans, nuts, or seeds forms a whole protein.

Protein cannot be stored in the body for future use, so we need to replenish our supply every day. Most Americans consume twice the protein they need. When more protein is taken in than the body can use, the excess is either burned off as energy or stored in the body as fat.

Fats

Fat is the most concentrated form of energy available to us and is necessary for growth and healthy function. As babies and children, we needed fat for brain development. As adults, many of us consume more than we need, which leads to weight gain and a national obsession about staying thin, especially for women. Conflicting cultural pressures make it difficult to obtain a realistic picture of the amount and types of fat we need.

Our body's fats are made up of fatty acids, which come in three major types: saturated, polyunsaturated, and monounsaturated.

Saturated fatty acids come from meats (e.g., beef, lamb, veal, pork), egg yolks, dairy products (e.g., cream, whole milk), and a few plant products, including coconut oil and vegetable shortening. The liver turns saturated fat into cholesterol, which is used to make cell membranes, hormones, and vitamin D.

Cholesterol travels through the body in the form of lipoproteins. Low-density lipoproteins (LDLs, or “bad cholesterol”) contain large amounts of cholesterol, whereas high-density lipoproteins (HDLs, or “good cholesterol”) carry relatively little cholesterol and help remove excess cholesterol from blood and tissues. If the LDL level is too high for the HDLs to clear away the excess cholesterol, it forms plaque on the artery walls, which can lead to heart disease.

Polyunsaturated fatty acids (PUFAs) are found in corn, soybean, safflower, and sunflower oils and some fish oils. PUFAs may actually lower “bad” cholesterol levels, but they have a tendency to lower HDL levels as well, leaving the body less capable of removing the amounts of cholesterol that are present. Although not as harmful as the saturated type, PUFAs can pose a health risk if too many are used in the diet.

Monounsaturated fatty acids are found in olive, peanut, canola, and other vegetable and nut oils. These fats actually reduce LDL level slightly and do not reduce HDL level, so they may benefit the body when taken in moderation.

Many oils are actually a combination of these different types of fatty acids, but in general, one type predominates, which is how the oil is described on the food label.

The Whole Truth About Whole Milk

Cow's milk is the ideal food—for calves. When it comes to human infants, children, and adults, the milk issue is cloudy. Cow's milk is three times higher in protein than is human breast milk. In fact, human breast milk has among the lowest levels of protein of any milk from mammals. Among different animal species, the higher the growth rate of infants of that species, the high the protein content of the species’ milk. Survival among the young of most species requires rapid rates of growth and maturation. This is not the case for human infants, who grow more slowly and mature over a longer time period.

Not only does cow's milk have a higher total protein content, but the type of protein present is very different from that in human milk. Cow's milk is six times higher in casein protein (which has been shown to promote tumors in some laboratory animal experiments). Also, cow's milk is low in linoleic acid, which may be important for early human growth and health. For these reasons and more, cow's milk is not a good food for human infants. And there is no reason on earth to think that it should be.

Among adults around the world, it is rare in most populations to consume whole milk in the diet. However, in some parts of the world, dairy animal domestication represents a renewable resource for converting plants and grasses from the environment (which are inedible for humans) into usable human food sources. Humans can't digest or extract nutrients from many plants containing cellulose. And, in fact, neither can cows—by themselves. However, ruminants like cows have multiple stomachs, which allow bacteria present in them to ferment cellulose so that it can be digested. In the cow, it is converted to meat and milk. Even termites rely on bacteria in their digestive tracts to digest cellulose from the wood they eat. The use of domesticated animals to graze on grasses allows humans to survive in relatively harsh, dry environments where there may not be enough other food to eat. Dairy animal domestication can be traced back approximately 10,000 years to parts of the world now called the Middle East, where the use of these animals allowed humans to survive in areas where they otherwise might not.

Human digestive problems can also be caused by milk consumption, however. Milk contains lactose, or milk sugar, which can only be digested by a special enzyme called lactase that breaks down lactose. All infants have lactase to digest milk sugar. However, most adults in most populations lose the lactase enzyme when they get older (and no longer would normally be expected to drink milk). These adults are intolerant of milk because of the lactose, which they cannot digest. They experience indigestion, intestinal problems, and possible malnutrition from drinking milk. In the Middle East and the Mediterranean region, local cultures have developed processes that allow bacteria to break down lactose through fermentation. Thus, production of cheeses, yogurts, and other cultured dairy products allows people to eat dairy foods without getting the lactose in whole milk that causes digestive problems. In China and East Asia, there is no dairy production at all, and milk and milk products do not form any part of the diet. This raises a question: how do over 1 billion of the world's people get adequate calcium without dairy? (See later.)

Northern European adults generally have the lactase enzyme, which allows them to digest milk and its lactose sugar without digestive problems. But whole milk remains an unnecessary source of fat in what should be a beverage. It is hard for Americans to avoid too much fat in their foods, but to drink it in our beverages is really making it difficult.

But what about calcium? Don't we need to drink milk to get calcium ?

Milk as a Source of Calcium

Milk is a good source of calcium, but there are ways of getting dietary calcium while bypassing the cow. There is much evidence to suggest that humans do not build bone by milk alone. Dairy-free diets are not necessarily low in calcium. Other good sources of calcium in the diet include fish, some vegetables, grains, and seeds. Over 1 billion people in China somehow get enough calcium in the diet, although, as noted earlier, there is absolutely no dairy industry or dairy consumption there. The Chinese refer to butter and cheese as “animal secretion” when they encounter it. There are no words in Chinese for products that do not exist there. The Chinese also have high rates of lactose intolerance, which perhaps explains why a dairy industry never developed there. Perhaps the Chinese get enough calcium from eating bits of bone and sinew left behind in traditional preparations of (lean) meat dishes. Bone is the best source of calcium of all, whether people eat the bones of sardines or whether normally herbivorous animals consume bone. When deprived of calcium even cows (and other ruminants) will eat the bones of other animals (although they are normally vegetarian).

Proper calcium nutrition is dependent on getting enough calcium in the diet and having adequate vitamin D to absorb it from the gastrointestinal (GI) tract. Vitamin D must be activated by sunlight on the bare skin to be effective (see the sidebar “The Light Cure and Vitamin D” in Chapter 11). So adequate calcium nutrition depends on the Gl tract, liver, kidneys, bone, and skin cells. Vitamin D deficiency became a problem in many people when populations moved into dark urban centers during the Industrial Revolution in the last two centuries. People no longer got enough fresh vegetables (since they had left the farms) and they did not get enough sun because they were kept indoors. The result was high rates of rickets.

Plants naturally contain vitamin D sources, which normally are eaten but then must be activated by sunlight in the skin cells. This is the kind of vitamin D usually contained in cow's milk, which comes from plants eaten by the cow. Today, milk does contain artificially activated vitamin D that does not require conversion by sunlight in the skin. However, with enough consumption of vegetables and adequate exposure of the skin to sunlight, it should be possible for most people to get adequate amounts of vitamin D.

Other Problems with Milk—Nothing to Sneeze At

Beyond the nutritional consequences of milk, cow's milk proteins may produce allergies in infants and children, which may threaten proper growth and be present for life. These infant allergies may have long-lasting effects on the immune systems. Many have noted an increase in adult allergies, which have been blamed on all manner of modern pollutants and allergens. I have wondered whether a whole generation of infants raised on the “enlightened” practice of bottle feeding with cow's milk are now a generation of adults with lifelong allergies.

Certified raw milk has also been found to be contaminated with Listeria, a dangerous bacteria responsible for the deaths of infants and children and harm to pregnant women. Historically cows and cow's milk have been carriers of diseases, including tuberculosis. The reason milk requires pasteurization is that it can be contaminated with dangerous bacteria. Some of my own research into the history of diseases shows that human tuberculosis may have originated with contact between humans and cows beginning 10,000 years ago.

The health costs of cows are real (not to mention the environmental costs). Today the risks of chronic disease from excess consumption of fats and proteins, as present in whole milk, are becoming clear for adults. The risks to infants are obvious. Failure to breastfeed in infancy often leads to overnourished and overweight infants. Human infants given cow's milk are by definition overfed. This overfeeding during infancy may cause excess fat deposition and increase body mass. These problems may have long-lasting consequences.

Americans still drink much more whole milk than other low-fat varieties such as skim. Substitute skim milk for whole milk and learn to like it. Drinking liquid fat (whole milk) has got to be an acquired taste. Better yet, cast off cow's milk. And by all means, for infants, breast is best.

Vitamins

In 1913, American biochemist Elmer McCollum became the first scientist to isolate a vitamin. Further research revealed that this substance, which became known as vitamin A, helps maintain skin, teeth, bones, hair, mucous membranes, and reproductive capacity. We can obtain vitamin A from cream, butter, egg yolks, cod liver oil, and some leafy green and yellow vegetables, or we can simply take a pill containing vitamin A. This is the great vitamin debate: for decades scientists have been arguing about whether supplements containing vitamins and minerals are a useful addition to the diet or whether we can and should obtain all the vitamins and minerals we need from the foods we eat.

No one disputes the need for vitamins, which enable us to make use of the energy stored in food to perform a variety of functions, ranging from maintaining the nervous system to forming red blood cells. There are two main categories of vitamins: fat soluble and water soluble. The fat-soluble vitamins, including A, D, E, and K, can be stored in the body's fat for days or weeks, whereas water-soluble vitamins dissolve quickly in the bloodstream and are removed in urine or sweat. Because water-soluble vitamins cannot be stored, these vitamins need to be resupplied on a daily basis. The most essential water-soluble vitamins are B1, B2, B6, B12, folic acid, C, niacin, pantothenic acid, and biotin.

There is some controversy about how much of each vitamin we need to stay healthy. The U.S. Food and Drug Administration has issued guidelines based on the National Academy of Science's recommended daily allowances (often listed on supplement labels as RDAs). Some consider these numbers the minimum needed to maintain health, whereas others maintain that these are maximum amounts that should not be exceeded.

Vitamin C, one of the most popular and widely debated vitamins, provides a good example of these divergent views. The RDA for vitamin C is 60 mg/day, the amount found in a single orange. Consuming less than this amount compromises the immune system, bones, and skin and even the ability to reproduce. Researchers at the University of California at Berkeley and the USDA's Western Human Nutritional Research Center determined that without 60 mg of vitamin C per day, waste products of metabolism known as free radicals can damage DNA. This can lead to cancer, heart disease, and other illnesses in all of us. For would-be fathers, this means sperm may contain genetic mutations that can result in birth defects, genetic disease, and cancer in future children.

Since the amount of vitamin C in a single orange can prevent all that, what can larger amounts do?

Linus Pauling, winner of Nobel prizes for chemistry and peace, would respond that megadoses of vitamin C can fight colds and boost the immune system. He consumed 300 times the recommended amount, about 18,000 mg, every day. Because vitamin C is water soluble, he pointed out, any excess will wash out harmlessly in the urine. Some scientists argue that our physiology and metabolism may not be equipped to handle micronutrients at levels higher than could be found in nature. Many complementary and alternative medicine practitioners take the middle path, advocating 300 to 3000 mg of vitamin C per day.

Then there is the real controversy: are you better off eating oranges or taking vitamin C tablets? To some extent, that depends on where you stand in the dosage debate; eating 1 orange a day is manageable, eating 300 is not. As we learned with limes, natural foods are complex arrangements of ingredients that tend to work best together rather than in isolation or synthesized form. We have identified a number of vitamins and their uses but may be far from understanding the full range of benefits we obtain from whole foods. Most physicians recommend receiving vitamins from a healthy diet. This is good advice, but in a nation earning a C− in nutrition, not very realistic. If your intake for the day consists of frozen waffles and coffee for breakfast, a hot dog with fries and cola for lunch, and pizza for dinner, you are probably going to miss a few nutrients. The most practical approach is to eat the best diet possible and take a multivitamin (without iron) as a “backstop,” for those days when life is too hectic to squeeze in even a single orange.

TABLE A Acute and Chronic, Major and Minor, Effects of Hypervitaminosis A

Minor

Major

Acute

Dryness of skin and mucous membranes

Eye, gastrointestinal, muscle complaints

Tenderness of long bones

Headache, drowsiness, irritability, nausea and vomiting

Redness and loss of skin on the face, trunk, palms, soles

Chronic

Reproductive and embryological abnormalities

Liver toxicity

Serum lipid abnormalities

Skeletal abnormalities

Vitamin A

The medical world has been very vigilant about the possible toxicity of micronutrients (see later) while remaining reluctant to embrace the evidence that optimal levels of micronutrients to help prevent or treat diseases are higher than the well-established RDAs. Vitamin A is a particular example. Because it is a fat-soluble vitamin, excess intake is not readily eliminated, which leads to the possibility of toxicity. Today, although reports of hypervitaminosis A are rare, deficiency of vitamin A is common and can even be considered an epidemic in certain portions of the world population.

National data from the American Association of Poison Control Centers repeatedly fail to show even one death from vitamin A per year. Vitamin A is very safe. However, pregnancy is a special case in which prolonged intake of too much preformed oil-form vitamin A might be harmful to the fetus, even at relatively low levels (under 20,000 IU/day). Interestingly, you can get over 100,000 IU of vitamin A from eating only 7 oz of beef liver. Have you ever yet seen a pregnancy overdose warning on a supermarket package of liver?

In fact, lack of vitamin A, especially during pregnancy and in infancy, poses far greater risks. Deficiency of vitamin A in developing babies is known to cause birth defects, poor tooth enamel, a weakened immune system, and literally hundreds of thousands of cases of blindness per year worldwide. This is why developing countries safely give megadoses of vitamin A to newborns.

Vitamin A Metabolism

Vitamin A (retinol) functions as a constituent of visual pigments, allows for normal reproductive capacity in both males and females, and permits normal cellular growth and differentiation. Among micronutrients, only retinol and its chemical derivatives can serve all of these biological functions.

The fat-soluble substance essential for normal growth that we now call vitamin A was recognized in 1909 and named in 1920, of. Preformed vitamin A, or the aldehyde and alcohol forms and their esters, are found mainly in animal products, including milk, eggs, meat, and fish, and is not synthesized by plants. However, provitamin A, which includes β-carotene among several other carotenoids, is found in plant sources and cannot be synthesized either by humans or animals. Both forms are also commonly found in over-the-counter pharmaceutical compounds. For the most part, β-carotene is converted to vitamin A during absorption through the intestinal mucosa, where it and preformed vitamin A are transported in the plasma by lipoproteins. Vitamin A is then stored in the liver in fat cells.

Wolbach and Howe (1925) were the first investigators to discover a relation between vitamin A and neoplasia; that is, dietary deficiencies in rats led to “preneoplastic abnormalities,” and restoration of vitamin A to their diet reversed the neoplastic process.

Many subsequent studies, including that in 1941 by Abels et al which associated vitamin A deficiency with human cancer, strongly supported the link between vitamin A and neoplastic disease. Recognition that vitamin A deficiency leads to abnormal growth of the skin and to preneoplastic changes spurred an initial rush to treat skin disorders with this new drug; however, early excitement was tempered because of toxic effects in many patients, especially liver toxicity.

Toxicity

A hominid or prehuman skeleton of Homo erectus (approximately 100,000 years ago) discovered in Kenya exhibited the earliest pathologically documented changes consistent with chronic excessive intake of vitamin A, or hypervitaminosis A. The clinical effects of excessive intake of vitamin A were first reported over 100 years ago, many years before vitamin A itself had even been positively identified. These reports involved the ingestion of polar bear and seal livers (5 to 8 mg retinal per gram of liver) by Eskimos and Arctic explorers. Their acute symptoms included severe headaches, drowsiness, irritability, nausea, and vomiting. Twelve to 24 hours after ingestion, redness and loss of the skin of the face, trunk, palms, and soles developed. Seven to 10 days later, all symptoms resolved.

Subsequent clinical observations verified these major acute symptoms of hypervitaminosis A, which occur when the intake of vitamin A exceeds the capacity of the liver to remove and store it, and after ingestion of a dose of at least 350,000 IU of vitamin A by infants and 1,000,000 IU by adults. Minor acute side effects are more frequent and better described. They include dryness of skin and mucous membranes as well as ocular, gastrointestinal, and musculoskeletal complaints such as tenderness of long bones. Specific major chronic vitamin A toxicities include abnormalities of the following: embryological development, reproductive function, serum lipids, liver function, and the skeletal system. Minor chronic side effects resemble the minor acute toxicities described earlier but are more subtle. (See Table A.)

Micronutrient Interactions

The principal micronutrients shown to interact with vitamin A are selenium, zinc, vitamins E and C, and iron. Selenium is an effective cancer-preventive agent in its own right, and its mechanism of action may be similar to that of vitamin A

Several studies have indicated that interactions occur between zinc and vitamin A at many levels of cellular activity. Some human enzyme systems requiring zinc are directly and indirectly critical to vitamin A metabolism. Zinc reportedly influences the enzyme that catalyzes the conversion of retinaldehyde to retinoic acid. Indirectly, zinc may affect vitamin A through zinc-dependent enzymes, which may be involved in the synthesis of vitamin A carriers and cellular binding proteins.

Research suggests that interactions occur between both vitamins C and E and vitamin A. Some investigators believe that vitamin E has only a nonspecific, antioxidant role in its relationship with vitamin A. Vitamin E stabilizes cell membranes, and vitamin E deficiency shortens the survival time of red blood cells and accelerates the depletion rate of liver stores of vitamin A. Vitamin E provides vitamin A and carotenoids with protection from oxidation in mixed diets. This protection results in higher levels of liver vitamin A and, under certain circumstances, higher circulating vitamin A levels. Studies of vitamin E–deficient rats fed vitamin A indicate that vitamin E protects vitamin A at a cellular level as well. Vitamin E may also reduce vitamin A toxicity.

Vitamin A deficiency and excess appear to influence the liver's synthesis of vitamin C (ascorbic acid), and vitamin C apparently acts as an antioxidant for vitamin A. Some reports claim to demonstrate a direct association between vitamin A deficiency and vitamin C synthesis.

High levels of iron in the intestine may contribute to destruction of vitamin A–active compounds. However, no data indicate that intake of high levels of inorganic iron causes vitamin A deficiency. Studies of human volunteers have revealed that vitamin A deficiency produces the gradual onset of anemia that responds to vitamin A but not to medicinal iron supplementation. Nutrition surveys commonly reveal an association between anemia and inadequate dietary vitamin A.

Epidemiological studies of children in developing countries showed a parallel increase in hemoglobin and serum iron levels with increasing blood levels of vitamin A. Experimental studies of the interaction between iron and vitamin A show that iron absorption is not altered by vitamin A deficiency and that vitamin A appears to help mobilize stored iron and incorporate it into red blood cells.

Vitamin A: Cancer Cure or Cancer Cause?

A few researchers have claimed that vitamin A, in test-tube experiments, will push stem cells to change into cells that can build blood vessels. They contend that this activity may increase cancer. When structures similar to blood vessels developed within the tumor masses grown in culture, the investigators concluded that vitamin A promotes carcinogenesis. However, an in vitro (test-tube) experiment is far from clinical proof. Even the study authors admit that vitamin A is known to be necessary for embryonic development precisely because it helps to differentiate stem cells, pushing them to become normal tissue—which is fundamentally an “anticancer” activity.

There is an anticancer drug that specifically acts by blocking the breakdown of retinoic acid, derived from vitamin A. This approach has been found to be effective in treating animal models of human prostate cancer. Daily injections of the agent VN/14-1 resulted in up to a 50 percent decrease in tumor volume in mice implanted with human prostate cancer cells. No further tumor growth was seen during the 5-week study. It seems that when cancerous tumors have more vitamin A available, they shrink. Keeping more retinoic acid available within cancer cells redirects these cells back into their normal growth patterns, which includes programmed cell death. This potent agent causes cancer cells to differentiate, forcing them to turn back to a noncancerous state. Vitamin A seems to induce positive, healthy, cell changes. Vitamin A derivatives are already in wide use to fight skin cancer.

Sensational warnings and outright misstatements that natural vitamin A may “incite” cancer actually serve to excite newspaper readers and television viewers. Upon closer examination, a “vitamin promotes cancer” study often has the appearance of being conducted to prove an intended point. As the authors fuel fears about vitamin A, they also give away their goal, stating that these findings open a new door to drug development. New marketing avenues for the development of patentable vitamin A–like drugs are a commercial opportunity that the pharmaceutical industry has not overlooked.

A vitamin A derivative could protect against lung cancer development in former smokers, says another report. Significantly, the vitamin A derivative is used in combination with α-tocopherol (vitamin E) to reduce toxicity known to be associated with 13-cis-retinoic acid (the vitamin A derivative) therapy. This point illustrates why nutritional physicians do not use high doses of vitamin A by itself, but rather give it in conjunction with other important, synergistic nutrients. All nutrients are needed in a living body.

The following is an example: A study published in the Journal of Nutritional Biochemistry found that administering both vitamin A and vitamin C to cultured human breast cancer cells was more than three times as effective as administering either compound alone. The combination of the two vitamins inhibited proliferation by over 75% compared with untreated cells. The ability of retinoic acid (vitamin A) to inhibit tumor cell proliferation is well known, although its mechanism has not been defined. The authors suggested that the synergistic effect observed in this study was due to ascorbic acid's ability to slow the degradation of retinoic acid, thereby increasing vitamin A's cell proliferation inhibitory effects. Vitamin C helps vitamin A work even better.

Doctors’ experience and clinical evidence both show that vitamin A helps prevent cancer, which has been known for a long time. The association of vitamin A and cancer was initially reported in 1926 when rats, fed a vitamin A–deficient diet, developed gastric carcinomas. The first investigation showing a relationship between vitamin A and human cancer was performed in 1941 by Abels et al, mentioned earlier, who found low plasma vitamin A levels in patients with gastrointestinal cancer. My colleague Tom Moon and his associates reported that daily supplemental doses of 25,000 IU of vitamin A prevented squamous cell carcinoma. And de Klerk et al reported findings of significantly lower rates of mesothelioma among subjects assigned to receive retinol. Studies in animal models have shown that retinoids (including vitamin A) can act in the promotion-progression phase of carcinogenesis and block the development of invasive carcinoma at several epithelial sites, including the head and neck and lung. The Linus Pauling Institute states that studies in cell culture and animal models have documented the capacity for natural and synthetic retinoids to reduce carcinogenesis significantly in the skin, breast, liver, colon, prostate, and other sites.

There will always be people bent on believing that vitamins must be harmful somehow. For them, it only remains to set up some test tubes to try to prove it. Such has been done with other vitamins, perhaps most notably a famous experiment that claimed that vitamin C promoted cancer. The study, reported in New Scientist, September 22, 2001, was a prime example of sketchy science carelessly reported. The article would have readers uncritically extend the questionable findings of a highly artificial, electrical-current-vibrated quartz crystal test tube study and conclude that 2000 mg of vitamin C can (somehow) do some sort of mischief to human DNA in real life. If 2000 mg of vitamin C was harmful, the entire animal kingdom would be dead. Our nearest primate relatives all eat well in excess of 2000 mg of vitamin C each day. And, pound for pound, most animals actually manufacture from 2000 to 10,000 mg of vitamin C daily, right inside their bodies. If such generous quantities of vitamin C were harmful, evolution would have had millions of years to select against it. The same is true for vitamin A. If it “promoted” cancer, every animal eating it would get cancer.

They don't, of course. And if we consume enough vitamin A, perhaps neither do we. The National Institutes of Health state that dietary intake studies suggest an association between diets rich in β-carotene and vitamin A and a lower risk of many types of cancer. A higher intake of green and yellow vegetables or other food sources of β-carotene and/or vitamin A may decrease the risk of lung cancer. A study of over 82,000 people showed that high intakes of vitamin A reduce the risk of stomach cancer by one half. Dr. Jennifer Brett comments that “vitamin A fights cancer by inhibiting the production of DNA in cancerous cells. It slows down tumor growth in established cancers and may keep leukemia cells from dividing.” A derivative of the vitamin has been shown to kill CEM-C7 human T lymphoblastoid leukemia cells and P1798-C7 murine T lymphoma cells.

Vitamin A is very far from being a cancer “promoter.” Rather, it may be very near to a cancer solution.

Vitamin D

The term vitamin D actually refers to a pair of biologically inactive precursors of a critical micronutrient. They are vitamin D3, also known as cholecalciferol, and vitamin D2, also known as ergocalciferol.

Cholecalciferol (D3) is produced in the skin by a photoreaction on exposure to ultraviolet B light from the sun (wavelength 290 to 320 nm). Ergocalciferol (D2) is produced in plants and enters the human diet through consumption of plant sources.

Sources and photoconversion of vitamin D. (Original artwork by Marc Micozzi, redrawn by Elsevier.)

Once present in the circulation, both D2 and D3 enter the liver and kidneys, where they are hydroxylated to form both 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D. The former, 25-hydroxyvitamin D, is relatively nonactive and represents the storage form of vitamin D. By contrast, 1,25-dihydroxyvitamin D is highly active metabolically, and its levels are tightly controlled. Vitamin D has many critical metabolic functions. There has been recent confusion in the literature regarding differences in relative abundance, availability and effects of vitamin D2 and D3, which have been reconciled by thoughtful investigation.

The major circulating form of vitamin D3 in human blood is 25-hydroxyvitamin D3, and therefore it is the form measured by physicians to evaluate vitamin D status in people worldwide. It takes a long time for this form to work on calcium absorption and mobilization, however, and it must be converted or metabolized to the more active 1,25-dihydroxyvitamin D for effectiveness in the body.

Knowledge of the role of vitamin D metabolic activity, its role in human health, and identification of the forms and metabolic pathways for vitamin D had been building for many decades but only became fully elucidated during the 1970s. Although nutrition is fundamental in human health, understanding of nutritional metabolism has generally lagged behind the pace of medical investigation and practice focusing on factors external to the host such as infectious microorganisms.

Versatility of Vitamin D

The first major functions of vitamin D to be recognized were (1) enhancement of calcium absorption from the diet through the intestine and (2) mobilization and reabsorption of calcium from bone, which represents the major store of calcium (or “calcium bank”) in the body. (See figure.) Calcium in turn is critical for cellular metabolism and membrane actions, enzymatic reactions, muscle function, skeletal structure, and a host of activities needed to sustain life and maintain homeostasis. Because vitamin D has long been recognized for its role in calcium metabolism, it has long been used to treat patients with renal failure and bone diseases. It also has an important role in the treatment of postmenopausal osteoporosis and the current epidemic of bone fractures in the elderly.

In 1979, however, DeLuca found that vitamin D is actually recognized by every tissue in the body. Every cell has receptors for vitamin D. Since then vitamin D has been used to treat hyperproliferative skin diseases such as psoriasis.

In the immune system, the large white blood cell macrophages activate vitamin D. The activated vitamin D in turn causes macrophages to make a peptide that specifically kills infective agents such as tuberculosis mycobacteria. Vitamin D also has a role in helping prevent autoimmune diseases such as multiple sclerosis, rheumatoid arthritis, and diabetes type 1.

Vitamin D's activity in the kidney has long been recognized, and it has been found to affect the production of renin and angiotensin, the major regulators of blood pressure, in the kidney. There is a direct correlation between higher (further from the equator) latitudes (where both sunlight and vitamin D levels are lower) and higher blood pressure in both the northern and southern hemispheres of the earth. People at high latitudes with high blood pressure experience a return to normal blood pressure levels after exposure to ultraviolet B light in a tanning bed three times a week for 3 months and restoration of active vitamin D levels (and you thought it only worked if the sunlight was captured on a beach in the Bahamas!).

Multiple sclerosis also shows a marked association with higher latitudes worldwide, and there may be a similar protective role for vitamin D for this disease.

Vitamin D is also thought to have an important role in cancer. As early as the 1940s it was noted that living at higher latitudes is associated with a higher incidence of several cancers (whereas only skin cancer specifically has a lower incidence at higher latitudes). Recent epidemiological observations have continued to bear out this association. A high frequency of sunbathing before age 20 was found to reduce the risk of non-Hodgkin lymphoma. And, although sun exposure is related to an increased incidence of malignant melanoma, it was also found to be associated with increased survival from melanoma in a recent study. In some of the sunniest spots on earth, both the Australian College of Dermatologists, the Cancer Council of Australia, and the New Zealand Bone and Mineral Society have concluded that a balance is required between avoiding an increased risk of skin cancer and achieving enough ultraviolet light exposure to maintain adequate vitamin D levels.

As in all things involving nutrition, achieving a balance is a good goal and guide for optimal health. It was thought that a balanced approach to this problem could be achieved through thoughtful dermatological screening for skin cancers. Thus, most skin cancers should be detected and treated early, because they are by definition visible on the surface of the skin, unlike cancers of other tissues, which begin growing hidden and undetected deep inside the body.

Dermatological intervention also took another, different direction, however. Rather than just focusing on early detection and treatment of skin cancer, dermatologists began fighting against the sun. That, in turn, has had profound effects on vitamin D nutrition and deficiency over the past 40 years.

Global Dimensions of D-ficiency

Essentially little or no active vitamin D is available from regular dietary sources. It is principally found in fish oils, sun-dried mushrooms, and fortified foods like milk and orange juice. However, many countries worldwide forbid the fortification of foods. There is potentially plenty of vitamin D in the food chain, because both phytoplankton and zooplankton exposed to sunlight make vitamin D. Wild-caught salmon, which feeds on natural food sources, for example, has available vitamin D. However, farmed salmon fed food pellets with little nutritional value have only 10% of the vitamin D of wild fish. The “perfect storm” of photophobia, lack of exposure to sunlight, and insufficiency of available dietary vitamin D has led to a national and worldwide epidemic of vitamin D deficiency.

Estimates are that at least 30% and as much as 80% of the U.S. population is vitamin D deficient. In the United States, at latitudes north of Atlanta, the skin does not make (photoconvert) any vitamin D from November through March (i.e., essentially outside of daylight savings time; so although we shift the clock around, it does not salvage vitamin D synthesis). During this season the angle of the sun in the sky is too low to allow UVB light to penetrate the atmosphere, and it is absorbed by the ozone layer. Even in the late spring, summer, and early fall, most vitamin D is made between 10 am and 3 pm when UVB from the sun penetrates the atmosphere and reaches the earth's surface.

It might be expected that vitamin D deficiency would be a problem limited to northern latitudes.

In Bangor, Maine, among young girls 9 to 11 years old, nearly 50% were deficient at the end of winter and nearly 20% remained deficient at the end of summer. At Boston Children's Hospital, over 50% of adolescent girls and African American and Hispanic boys were found to be vitamin D deficient year round. In another study in Boston 34% of whites, 40% of Hispanics, and 84% of African American adults over age 50 were found to be deficient.

Vitamin D deficiency is also a national problem, however. The U.S. Centers for Disease Control and Prevention completed a national survey at the end of winter and found that nearly 50% of African American women aged 15 to 49 years were deficient. These are women in the critical childbearing years. A growing fetus must receive adequate vitamin D from the mother, especially because breast milk does not provide adequate vitamin D. A study of pregnant women in Boston found that in 40 mother-infant pairs at the time of labor and delivery, over 75% of mothers and 80% of newborns were deficient. This observation was made despite the fact that pregnant women were instructed to take a prenatal vitamin that included 400 IU of vitamin D and to drink two glasses of milk per day.

Further, vitamin D deficiency is a global problem. Even in India, home to 1 billion of the earth's people, where there is plenty of sun, 30% to 50% of children, 50% to 80% of adults, and 90% of physicians are deficient. In South Africa, vitamin D deficiency is also a problem even though Cape Town is situated at 34 degrees latitude.

Although there are many new bilateral and multilateral governmental and private efforts to export Western medical technology and pharmaceuticals to the Third World to combat infectious diseases such as acquired immunodeficiency syndrome (AIDS), there is no comparable effort to acknowledge and address the global dimensions of the vitamin D deficiency epidemic. The U.S. Congress and president just deemed it as a great achievement to give $40 billion in tax dollars to U.S. pharmaceutical companies to send expensive drug treatments for AIDS (a preventable disease) overseas. By contrast, addressing the vitamin D deficiency epidemic could be accomplished with much safer and less expensive nutritional supplements together with sunlight, the only source of energy that is still free.

Vitamin D Dose, Toxicity, and Formulation

It has been well established that giving 100 IU of vitamin D daily to children will prevent rickets (Table B).

As with most of established thinking about recommended daily allowances (RDAs), the dosages are those that prevent the development of frank nutritional deficiencies and associated pathology. The idea of levels for optimal health does not enter the picture. Even the capricious RDA process raised the recommendation from 200 IU to 400 IU/day in 1997 (although technically it is not an “RDA” but an “IA,” or adequate intake).

Currently, those more knowledgeable about human nutrition than the group involved in the outdated RDA/IA process recommend 1000 IU daily for both children and adults to maintain blood levels of 25-hydroxyvitamin D above 30 ng/mL. It is now recognized that each 100 IU of vitamin D ingested raises blood levels by only 1 ng/mL (Table C).

TABLE C Blood Levels of Vitamin D (25-Hydroxyvitamin D)

Level (ng/mL)

Associated intakes and effects

1

Amount blood level is raised by 100 IU intake

1-20

Deficiency

21-29

Insufficiency

30-150

Sufficiency, reached by 50,000 IU weekly for 8 weeks

50

Reduces risk of breast cancer by 50% (vs. 20 ng/mL)

150-200

Onset of toxicity

TABLE B The Evolving Picture of Vitamin D Daily Intake

Daily intake

Associated effects

100 IU

Prevents rickets, frank nutritional deficiency disease

Amount in one glass of milk or fortified orange juice

200 IU

“Adequate intake” per RDA pre-1997

400 IU

“Adequate intake” per RDA post-1997

Reduces risk of rheumatoid arthritis in women by 50%

1000 IU

Reduces risk of cancer (breast, colorectal, ovarian, prostate) by 50%

2000 IU

Reduces risk of diabetes by 80%

Reduces incidence of upper respiratory tract infections in the elderly by 90%

Reduces PSA levels in men by 50%

30,000 IU

Minimum to develop toxicity over several months or years

PSA, Prostate-specific antigen; RDA, recommended daily allowance.

Although a typical recommendation is in the range of 1000 to 2000 IU/day, it is reasonable to recommend up to 5000 IU/day.

It is not easy to become vitamin D intoxicated. Sunlight actually destroys any excess vitamin D that is made in the body, so it is not possible to become vitamin D intoxicated from too much sunlight alone. In a world in which dangerous and expensive drugs are doled out like candy, it is ironic to witness the degree of concern in the medical establishment over exposures to physiological levels of natural substances such as vitamins, and even sunlight!

Nonetheless, a medical lore has developed over the possible risks of excess vitamin D intake, although vitamin D intoxication is one of the most rare medical conditions in the world. If vitamin D were considered as a drug, it demonstrates a remarkably high therapeutic index of at least 300 for disease treatment (ratio of minimum toxic dose to dose given to treat rickets) and at least 20 for chronic disease prevention. If the patient has a chronic granulomatous disorder such as histoplasmosis, sarcoidosis, or tuberculosis, however, a vitamin D blood level above 30 ng/mL will cause hypercalcemia and hypercalciuria. Therefore, supplementation should be avoided in these cases.

Because the only pharmaceutical preparation of vitamin D is in 50,000-IU doses, one therapeutic regimen is 50,000 IU per week for 8 weeks to treat deficiency, with 50,000 IU every 2 weeks thereafter for maintenance of adequate vitamin D levels. Dietary supplements are also good choices for vitamin D.

Manufacturers often add 50% more vitamin D than is listed on the label to maintain potency during the shelf life of the product. Thus, a 1000-IU formulation that actually contains 1500 IU is still perfectly safe.

Despite the inadequacy of the RDA/IA process there is ample evidence and clinical experience indicating that vitamin D blood levels and daily intakes should be much higher than they are, not only for prevention of bone diseases but to provide optimal health and help reduce the risk of many common chronic diseases, disorders, and medical conditions. Together with healthy sun exposure, Vitamin D supplementation can be accomplished safely and effectively and should be a first-line consideration in any clinical practice and for the general population.

Minerals

Minerals are everywhere in nature and range from beneficial (calcium) to poisonous (arsenic). The minerals essential to human function include calcium, phosphorus, potassium, sodium (salt), chloride, and magnesium. In addition, we need a number of trace elements, including iron, zinc, selenium, manganese, copper, iodine, molybdenum, cobalt, chromium, and fluorine. As with vitamins, most physicians recommend obtaining minerals from a healthy diet, whereas many complementary and alternative medicine practitioners advocate supplements to ensure a regular supply.

RDAs have been established for only six minerals—calcium, phosphorus, iron, magnesium, iodine, and zinc—and two of those guidelines have recently been questioned. Much recent publicity has surrounded the role of calcium in preventing osteoporosis, the brittle bones that come with age, especially for women. The National Academy of Science recently raised the RDA for calcium from 800 to 1000 mg for nonpregnant women and from 1200 to 1500 mg for pregnant women. Although this is a step in the right direction, compliance remains doubtful. The old RDAs were not met by 68% of the total population; more significantly, they were not met by 84% of women between ages 35 and 50 and 87% of girls between 15 and 18 years of age. With higher standards, these compliance percentages may slip still lower.

The one mineral that medical professionals have been successful in promoting, iron, has turned out to be potentially harmful. For many years, although expressing now-discredited concerns about potential dangers from most supplements, the medical profession advocated the use of iron supplements. Vital for the production of hemoglobin, which transports oxygen to the body's cells, iron is also necessary for many immune, growth, and enzyme functions. Lack of iron leads to anemia, especially in pregnant women, and to other conditions, including fatigue, fragile bones, and mental disorders. However, because iron is stored in the body, excesses can easily build up, causing the production of free radicals, which have been associated with cancer and heart disease. This author has conducted independent research showing that excess iron can cause cancer. More often, overuse of iron supplements causes digestive discomforts and disorders. Dietary guidelines for iron are now being revised downward, and many multivitamin supplements are now available without iron.

Exactly how much of any nutrient is needed depends largely on the physical condition of the individual. Pregnant women, athletes, smokers, people with chronic illnesses, and those of various ages and lifestyles all have different dietary requirements. The one dietary requirement that is relatively consistent for all of us is the need for water.

Water and Fluid and Electrolytes

The human body can survive up to 5 weeks without food but rarely lasts beyond a few days without water. Our bodies are almost 70% water, which is vital for every bodily process, including absorbing and digesting food, transporting nutrients throughout the body, and carrying out waste materials. Water is naturally lost through sweat and elimination. Caffeine, alcohol, and other constituents act as diuretics, which increase urination and further deplete the body's reserves of liquids. To replace all this lost fluid, we need to drink at least eight glasses of water a day. Dry mouth, headache, and fatigue are often signs we are dehydrated. Exercise, massage, and other activities increase our need for water. When we are ill, additional fluids help flush toxins from the body and restore well-being.

Fluid and electrolyte balance is critical for good health and physical performance. The salinity of the blood and tissues matches the salinity of the oceans at the time life is thought to have emerged from the sea into the terrestrial environment. Water itself has some unique properties that has enabled life to exist on earth. Liquids generally freeze from the bottom up; as liquids cool, the colder molecules of the liquid (with lower kinetic energy) fall toward the bottom because they become more dense—and thus the liquid will become solid (freeze) from the bottom up. Water, to the contrary, has a distinctive molecular configuration. As water cools the molecular configuration becomes more dense until it reaches approximately 40° F at which point a remarkable effect takes hold. The water molecules begin to lock into a molecular configuration that is less dense, and the molecules rise to the top as they freeze. In large bodies of water, the frozen layer at the top then tends to trap any heat energy in the lower reaches, thus preventing the entire body of water from freezing. Imagine the implications for life on earth if bodies of water froze from the bottom up.

Individual organisms rely on water to carry blood cells and nutrients to all parts of the body in the blood circulation, to bathe the tissue cells in extracellular fluid, to support the central nervous system through the cerebrospinal fluid, and to return excess body fluids to the circulation through the lymphatic vessels. It is one large, complex hydraulic system.

It is important to maintain both fluid and electrolyte levels. The formation of urine occurs at a relatively constant rate to filter the blood and remove metabolic by-products to eliminate them from the body. Although carbohydrate is broken down in the body to carbon dioxide (which is breathed out through the lungs) and water vapor (both breathed out and eliminated in urine), organic nutrients containing nitrogen must be eliminated as metabolic by-products and excreted through the urine. The fate of proteins, purines, and pyrimidines (nucleic acids) is ultimately to become urea and uric acid in the urine. Buildup of uric acid in the blood leads to gout with deposits of uric acid crystals in joints and cartilage (such as in the earlobes). In kidney failure, nitrogen-containing metabolites build up in the blood to the point that they cause central nervous toxicity (renal encephalopathy).

In addition to elimination of fluid and electrolytes in the urine, there are continual insensible losses of water through respiration (the exhaled air carries out water vapor) as well as losses of both water and electrolytes through sweating. Humans, who are less hirsute mammals, have sweat glands throughout the skin of the body. Cooling by evaporation of water allows the surface of the body to reduce surface temperature. Hairier animals covered with fur cannot use this mechanism and rely on hyperpnea, or rapid panting, which allows blood in the tongue to be cooled by contact with air (like the old air-cooled engines of the Volkswagen Beetle). When people sweat due to high ambient temperatures and/or high physical performance, it is important to replace both fluid and electrolytes.

Body water and electrolytes may also be lost by excretion of excessive fluids in the stool, as in diarrhea and dysentery (the latter implies loss of blood as well as water and electrolytes in the stool). In the case of cholera, the cholera bacteria produce a toxin that inhibits reabsorption of water from the intestinal contents by the cells lining the intestines. The result is massive fluid and electrolyte loss, which may result in death from dehydration within days. Diarrhea is still a very common cause of death in infants in third world countries, especially where nursing mothers are encouraged to use infant formula (made with contaminated water) instead of staying with the proven benefits of natural breastfeeding.

DIET AS THERAPY

Although most mainstream Western physicians receive little training in diet and rarely consider it as a therapy, many other health practitioners consider food a vital part of preventing and treating illness (see Chapters 21, 26, 29, and 32).

Chinese Medicine

Since ancient times, the Chinese have used food for medicinal purposes, and many contemporary medical schools include a classroom kitchen to train students in preparing beneficial foods. Families and some restaurants routinely prepare special dishes to meet the needs of people who are ill, elderly, pregnant, or lactating. Beneficial foods are identified and selected on the basis of such traditional Chinese medical concepts as the five-phase theory and yin and yang, two models for the dynamic processes governing the universe and human bodies. Yin is associated with the female principle, and its properties include cold, slowness, darkness, the interior, and deficiency. Yang is associated with the male principle; its properties include heat, light, speed, the exterior, and excess. A disease characterized by too much cold would be associated with yin, and a practitioner might prescribe foods and herbs that stimulate yang by enhancing heat or “scattering the cold” (see Chapter 26 and later section on macrobiotics).

Ayurveda

Developed in ancient India, Ayurveda (Sanskrit for “the knowledge of long life”) has always incorporated food into its holistic approach to health. In Ayurveda, three doshas (vata, pitta, and kapha) define the three basic mind-body or constitutional types. Each dosha finds certain foods and flavors beneficial, whereas others may be harmful if taken in too large a quantity. For instance, people whose dominant dosha is vata, which is responsible for the body's kinetic energy and associated with the element of air, may suffer from nervous energy and will be soothed by warm, moist, sweet foods and aggravated by pungent, bitter, raw foods. Following an appropriate vata diet can help people avoid or recover from a wide range of vata disorders, such as insomnia, constipation, anxiety, high blood pressure, and arthritis (see Chapters 29 and 32).

Naturopathy

A synthesis and refinement of nineteenth-century nature cures, naturopathy considers a wholesome diet one of the cornerstones of good health, along with exercise, fresh air, adequate sleep, and low-stress lifestyle. Naturopaths believe that the body has an innate tendency to heal itself and that nourishing food is necessary for the body's self-maintenance and repairs. Practitioners recommend a diet of whole (unprocessed) foods, especially fresh fruits and vegetables, which should be organic (free of chemicals and other additives) if possible. Fasting, including juice fasts, may be prescribed to rid the body of toxins. Naturopaths started the first “health food stores” in America and developed many foods, such as graham crackers, that were revolutionary in their use of whole grains (see Chapter 21).

Macrobiotics

Loosely based on the traditional Chinese concepts of yin and yang, the macrobiotic diet was developed in the 1950s by George Osawa, a Japanese educator and philosopher. The name is derived from the Greek makros (“big” or “long”) and bios (“life”), and its practitioners believe a long and healthy life can be achieved through a balanced diet and other beneficial practices. As do traditional Chinese physicians, macrobiotics advocates believe all foods have yin or yang properties. Yin foods, which are thought to be calming, include green vegetables, fruits, nuts, and honey. Yang foods, said to be strengthening, include meat, fish, eggs, and beans. Whole grains, which have balanced yin and yang, form the cornerstone of the diet. Too much yin food can leave a person feeling resentful and worried; an overly yang meal may generate feelings of aggressiveness. Eating the proper foods can help rebalance feelings and restore physical well-being.

Reversal of Heart Disease

Heart disease was considered irreversible until the 1980s, when cardiologist Dean Ornish proved that heart patients could restore heart health through diet, exercise, and stress management. Based on the Pritikin diet, Ornish's diet is very low in fat (perhaps too low at 15% of calories) and cholesterol and is high (perhaps too high) in carbohydrates and fiber. It excludes almost all animal products except for skim milk and fat-free yogurt. An occasional glass of wine is permitted; smoking is not. In a rigorous week-long training session, participants are taught how to cook and eat according to Ornish's guidelines and are instructed in exercise, yoga, and meditation. When they go home, they are expected to continue the regimen indefinitely. This approach is not easy to maintain, but when the alternative is heart bypass surgery, possibly followed by another operation in 5 years, participants are motivated; in 99% of cases, those who followed the regimen successfully reversed the course of their heart disease. Many who question whether the Ornish diet itself is optimal point to the benefits of social support and stress reduction to help account for these results.

Vegetarian and Vegan Diets

A vegetarian does not eat meat, poultry, or fish but does eat eggs and dairy products. Research has demonstrated that a vegetarian diet can reduce the risk of heart disease, high blood pressure, diabetes, osteoporosis, gallbladder disease, colon cancer, and other conditions. A vegan diet excludes all animal-based foods, including dairy products, eggs, and honey. Unless supplements are used, vegans risk deficiency of vitamin B12. The vegan diet has been used to treat asthma, arthritis, high blood pressure, and angina.

Raw Foods

In the late nineteenth century, Swiss physician Max Bircher-Benner developed a diet that is 70% uncooked vegetables and fruits; the balance of the diet can include meat, dairy products, grains, nuts, and seeds. He believed that raw foods (1) are more natural and appropriate for the human digestive system, (2) maintain their nutrients better than cooked food, and (3) prolong the life span.

Detoxification

Since ancient times, people have sought to eliminate toxins from the body by fasting and special diets, often in conjunction with other means, such as emetics and enemas. At present, many Americans are concerned about ridding their bodies of waste products that have accumulated because of poor digestion or sluggish elimination or that have resulted from environmental toxins. Practitioners recommend eating only raw fruits and vegetables and drinking large amounts of water; yogurt may also be included in the regimen (see also Chapter 21).

The Atkins Diet

In the 1970s, Robert Atkins developed a diet based on the principle that sugar and refined carbohydrates increase the body's production of insulin, a hormone necessary for the transformation of carbohydrates to blood sugar. Consumption of white bread, pasta, cereal, and other highly processed, low-fat foods causes insulin levels to spike. When the carbohydrates are absorbed and high amounts of insulin are no longer needed, insulin levels drop sharply, which reduces energy and encourages thoughts of a carbohydrate-laden snack. Atkins developed a diet that severely restricts the intake of processed and refined carbohydrates and promotes instead a diet focusing on “nutrient-dense” foods—proteins, fats, and complex carbohydrates—supported by multivitamins and other supplements (Atkins Center, n.d.). The Atkins diet has been demonstrated to be effective for short-term weight loss, but the long-term health effects are of concern to some.

The “Zone” Diet

Like Atkins, Barry Sears designed a diet that reduces the intake of processed foods and sugar to control insulin level. Sears's diet, which he calls “Zone Perfect” and most people know as “the Zone,” uses food as a drug to keep insulin levels in the “therapeutic zone” 24 hours a day. According to Sears, every meal and snack should contain a set ratio of macronutrients: 30% protein, 40% carbohydrates, and 30% fats. Sears also suggests adding supplements, such as ω-3 fish oils and antioxidants, to enhance the Zone diet (Zone Perfect, n.d.).

FOOD OR DRUG?

Sears and Atkins are not the only people using food's druglike properties to affect the body. Scientists have long been aware that many fruits, vegetables, grains, and beans appear to reduce the risk of heart disease, cancer, and other conditions because they contain antioxidants (vitamins, minerals, and enzymes that protect cells from being damaged by oxidation). Now another group of disease-fighting nutrients has been identified: phytochemicals, also known as “nutraceuticals.”

Phytochemicals are thought to fight cancer and other ailments by keeping disease-causing substances from latching onto healthy cells and by removing toxins before they can cause harm. There are many thousands of phytochemicals—tomatoes alone contain 10,000 different kinds—each with a slightly different function. Genistein, for example, which is found in soybeans, prevents the formation of the capillaries needed to nourish tumors. Indoles, which increase immune function, are found in members of the Brassica family such as broccoli and cauliflower. The bioflavonoids found in limes prevent certain cancer-causing hormones from attaching to the body's cells. Much as an earlier generation of scientists sought to identify and synthesize vitamins, today's researchers are working to isolate and manufacture phytochemicals. However, it is unlikely that they will be able to reproduce the rich mix of beneficial substances found in a single tomato or a handful of soybeans.

Sometimes we do not need to eat the plant to obtain the benefits of phytochemicals. For example, brewing teas such as green tea can provide a natural mixture of antioxidants to be drunk as a beverage. The antioxidant profile of green tea (from Asia) has been studied extensively in terms of its anticancer effects. A newly popular red tea (from South Africa) has a similar profile of antioxidants, but without the caffeine, and also shows anticancer properties.

FOOD ALLERGIES

Soybeans may be bristling with needed nutrients and phytochemicals, but they are among the common foods that trigger allergies. Other major offenders include nuts (especially peanuts), dairy products, fish, shellfish, wheat, eggs, and food additives, especially preservatives and coloring agents.

An allergy occurs when the immune system reacts to an ordinary food as if it were a hostile invader, producing an antibody known as immunoglobin E. This antibody attaches itself to specialized immune cells known as masts, and when the offending food is encountered again, the antibody causes the mast cell to release chemicals that produce the allergic reaction. The result may be skin disorders (e.g., hives, eczema), respiratory conditions (e.g., allergic rhinitis, asthma), stomach problems (e.g., cramps, diarrhea), or headaches. In severe cases, people may develop anaphylactic shock, which causes collapse and possibly even death.

No one knows for certain what causes allergies to arise, but it is common for them to run in families, although each family member may have a different type. Some theorize a possible psychological component; on some deep level, allergy sufferers may view the world as inherently hostile. “It is fairly common to be sensitive to one or two foods,” notes physician Christiane Northrup. “But women with multiple food allergies that are resistant to simple dietary change often have a history of abuse of some type, or they are continuing to live in dysfunctional relationships or to stay in overly stressful jobs” (Northrup, 1994).

Start with the Usual Suspects

The offending substance (known as an allergen) can often be identified by a simple skin prick test, in which one after another of the “usual suspects” is injected under the skin to see how the body responds. Another investigative technique is the radioallergosorbent test, in which blood is drawn, serum containing antibodies is extracted, and possible allergens are added to test for a reaction. Naturopaths favor an elimination diet, in which various foods are systematically removed from the menu for 2 weeks. When symptoms disappear, foods are reintroduced one by one until a reaction takes place, indicating which one is causing the allergy.

Herbalists often recommend that the elimination diet be accompanied by intake of immune boosters such as echinacea and red clover, digestive aids (e.g., slippery elm, marshmallow, hops), and dandelion root to support liver function (see Chapter 22). Yoga practitioners can teach postures designed to aid digestion and overall well-being (see Chapter 31). Nutritionists with expertise in supplements advise taking vitamins and minerals, including zinc, selenium, vitamin C, magnesium, and manganese.

Homeopaths treat allergies with a form immunotherapy in which highly diluted amounts of the allergen are given with the aim of overcoming the reaction (see Chapter 24). This is similar to the controversial approach known as desensitization, in which people are exposed to minute but increasing amounts of the allergen until a higher level of tolerance is achieved. Enzymes have proved effective in treating some milk sugar allergies. For the majority of those with allergies, the most effective treatment is avoiding the allergen in question.

FUNCTIONAL FOODS

The American food industry is currently responding to the public's desire for healthier fare by creating a variety of products that, they claim, provide enhanced health benefits, such as lowering cholesterol and heightening mental abilities. Known as functional foods, these products include snacks, cereals, margarines, and salad dressings laced with calcium, vitamins, fiber, and such new constituents as DHA (docosahexaenoic acid), which is currently being used in Japanese schoolchildren and is said to improve concentration.

To achieve the benefits of functional foods, large quantities of them must be consumed. One margarine, for example, must be eaten three times a day for 2 weeks to lower cholesterol by 10%. To obtain their full allotment of vitamins from snack foods, toddlers must eat three and a half cookies a day. Often six times as expensive as standard fare (e.g., one margarine retails for $17.22 a pound), these functional foods require a level of commitment many families are not prepared to make.

The greatest drawback to many functional foods is the flavor. As New York Times food critic William Grimes noted, one cholesterol-controlling apricot and orange cereal bar has the “texture of a rubber eraser, enlivened by a hideously artificial fruit flavor.” He noted that a “sugar controller” for diabetic patients, a fudge brownie flavor nutrition bar, “chews like a plug of tobacco, minus the flavor, except for a haylike aftertaste. The chocolate coating seems to be for color only. Nuts depicted on the wrapping fail to show up in the actual bar” (Grimes, 1999). In a taste test of 13 functional foods, five got a “thumb's up,” including the bone-building Aviva Instant Hot Chocolate and Viactiv's caramel-flavored soft calcium chews; the majority of products received a “thumb's down.” Grimes addressed the “pleasure principle” as follows:

All food is functional. That's why humans eat three times a day. But unlike animals and insects, they do not eat for function's sake alone. Somewhere in the tortured mental software that governs eating behavior, the pleasure principle lives in more or less uneasy proximity to the efficiency principle. We eat to live, but we also live to eat.

NUTRITION VERSUS NOURISHMENT

Food and emotions are very deeply linked in human beings for reasons far older than our current obsession with thinness. For centuries the human race was able to survive because we ate the things our tribes said were okay to eat. We avoided the poisonous berries and ate what Mother said was safe. Food has always been an essential part of the daily ritual of living, and the foods we were fed in childhood have left a very deep impression on us. At an unconscious and conscious level, they help us feel safe and cared for (Northrup, 1994).

One of the reasons diets and food fads are so popular is that we are tribal beings who take our cues about what to eat from those around us. One of the reasons diets so often fail is that they conflict with much deeper cultural programming that comes from our family of origin. If generations of your relatives served beef brisket (or borscht, or macaroni and cheese) for dinner every Sunday, that dish will forever be equated with family gatherings and feelings of belonging. However flawed they may be, our families usually present our strongest links to our past and to others; in a profound way, they represent safety and the sense of being at home.

Unfortunately, the eating patterns of the past do not always work well in the twenty-first century. The rib roast with gravy and buttered potatoes that once nourished our great grandparents on the farm may lead to a heart attack in someone whose most strenuous daily activity is booting up the computer. On the other hand, the food products our contemporary culture urges us to consume—loaded with fat, salt, sugar, artificial ingredients, and chemical additives and stripped of nutrients during processing—are equally unlikely to sustain us into a healthy and advanced old age. Taking a scientific, reductionist approach is not the answer either. Obsessing about every calorie and gram of fat on our plates can turn food into an enemy. Eating is one of the most vital ways we connect with our environment and with each other. Treating food as a hostile force is not good for our bodies, our souls, or our relationship with the world.

So, what is the key to healthy eating? Moderation and common sense are a good starting point. Once we understand our basic nutritional needs and which foods we would be wise to avoid when possible, we can move gradually into patterns of eating that provide us with a sense of physical well-being. However, unless we have a medical condition such as diabetes that requires strict dietary controls, healthy eating does not mean abandoning favorite foods forever. On occasion a piece of grandmother's fried chicken at a family gathering, an ice cream cone on a summer afternoon, or a mug of sugary cocoa after sledding is a necessary reminder that being alive is sometimes supposed to be fun and that sharing food with the people we love can be healthy for our hearts in ways not yet recognized by biomedical science. Food is rich in cultural, social, and personal meaning as well as nutrients, and all these elements are necessary for a balanced diet.

Chapter References can be found on the Evolve website at http://evolve.elsevier.com/Micozzi/complementary/ (Micozzi 355)

Micozzi, Marc. Fundamentals of Complementary and Alternative Medicine, 4th Edition. W.B. Saunders Company, 2011. VitalBook file.

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