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