Minerals
Chapter 8: Water and Minerals. Learning Objectives:
• Describe the roles of water in our body.
• Identify the minerals calcium and iron, mention their physiological roles in the body, the consequences of deficiencies, and their most important food sources.
– Explain why is important to fulfill calcium requirements.
– Compare the availability of iron from plant and animal sources.
• Identify the consequences of the excess of sodium in our diet and provide strategies to reduce sodium intake.
Introduction
• Water
– Most indispensable nutrient
• Minerals
– Major
– Trace
Water: A Crucial Nutrient
Functions: Maintain body temperature and electrolyte balance Transport nutrients Participate in many chemical reactions
dehydration, an abnormal
depletion of body fluids.
hyponatremia, a decreased concentration of sodium in the blood
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Water Balance – A Typical
Example
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Water in Foods and Beverages
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
U.S. Fluid Sources
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Liquid Calories
Weighing in on extra fluids
Added sugars
Drinking calories
Meeting the body’s fluid needs
Minerals in a 60-Kilogram (132-Pound) Person (Grams)
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
A Bone
Calcium – Blood calcium is tightly controlled in body fluids (1%)
– Roles: • Helps maintain blood pressure
• Regulate transport of ions across membranes (nerve transmission)
• Muscle contraction
• Blood clotting
• Calcium balance (intestines-bones-kidneys)
– Skeleton serves as a calcium bank • Bone density: a measure of bone strength, the degree of
mineralization of the bone matrix. Measured by DEXA.
Losses of Trabecular Bone
Loss of Height in a Woman Caused by Osteoporosis
Meeting the Need for Calcium
• Low calcium intake
– Associated diseases
• Milk, yogurt, & cheese group
– Traditional sources of calcium
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Calcium
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Sodium Intakes of U.S. Adults
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Sodium
Blood pressure
Hypertension
Prehypertension
Sodium intakes increases blood pressure
DASH diet
Controlling salt intakes
Processed foods
Fast foods
Read Nutrition Facts labels
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Sources of Sodium in the U.S. Diet
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Iron Two proteins: Hemoglobin and Myoglobin
Roles
Carry oxygen
Make new cells, amino acids, hormones, & neurotransmitters
Iron stores
A mineral to be tightly regulated
Iron losses
Special proteins transport and store iron
Absorbing iron
Forms of iron in food
MFP factor
Impairing iron absorption
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Promoters and Inhibitors of Iron
Absorption
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Iron
Deficiency
Iron deficiency
Iron-deficiency
anemia
Signs of deficiency
Mental symptoms
Adults
Children
Pica
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Normal and Anemic Blood Cells
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Iron
Causes of deficiency
Blood loss
Groups most susceptible to deficiency
Women of childbearing age
Infants, toddlers, adolescents
Too much iron
Iron overload
Symptoms
Recommendations
Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney
Iron