Chapter 8 Water and Minerals Nutrition: Concepts & Controversies, 12e Sizer/Whitney Introduction Minerals Major Trace Water Most indispensable nutrient Minerals in a 60-Kilogram (132Pound) Person (Grams) Water Makes up about 60 percent of a person’s weight Roles Solvent Cleansing agent Lubrication and cushion Coolant Body’s Water Balance Water balance Dehydration Thirst Signs Groups at risk Water intoxication Body water varies by pounds Thirst and satiety govern water intake Hypothalamus, pituitary gland, kidneys Water Balance – A Typical Example U.S. Fluid Sources Safety and Sources of Drinking Water Public water Removal of many hazards Disinfectants Testing and reporting Chlorination and cancer Water sources Surface water Groundwater Bottled Water Regulation and safety Sales across state lines Standards Less rigid than those for tap water BPA IBWA trademark Water for nutrition’s sake Fluoride Body Fluids and Minerals Water follows salt Electrolytes Water flows toward greater concentration Fluid and electrolyte balance Causes of imbalance Acid-base balance Hydrogen Buffers A Bone Calcium Bone and tooth formation Hydroxyapatite Fluorapatite Bone and tooth turnover Calcium In body fluids 1 percent of body’s calcium Roles Blood calcium is tightly controlled Calcium balance Skeleton serves as a calcium bank Bone density Organs Bone Throughout Life Calcium Snapshot Phosphorus Second most abundant mineral in body Majority found in bones with calcium Roles in the body Recommendations Deficiencies are unlikely Food sources Phosphorus Snapshot Magnesium “Major mineral” Dietary requirement Bones and kidneys Roles in the body Works with calcium Deficiency Toxicity Recommendations Magnesium Snapshot Sodium Roles Major part of fluid and electrolyte balance Acid-base balance Deficiency “Water Weight” Recommendations Intakes Sodium Blood pressure Hypertension Measures Types Sodium intakes increases blood pressure Heart damage DASH diet Controlling salt intakes How to Cut Sodium from a Barbeque Lunch Potassium Positively charge ion inside the cells Roles Fluid and electrolyte balance Heartbeat Deficiency Dehydration Toxicity Recommendations Potassium Snapshot Iodine Body’s work is done by iodide Roles Thyroxine Deficiency Goiter Cretinism Toxicity Food sources Iron Every living cell contains iron Two proteins Hemoglobin Myoglobin Roles Carry oxygen Make new cells, amino acids, hormones, & neurotransmitters Iron Iron stores A mineral to be hoarded Iron losses Special proteins transport and store iron Absorbing iron Forms of iron in food MFP factor Impairing iron absorption Normal and Anemic Blood Cells Iron Snapshot Zinc Works with proteins in every organ Roles Expression of deficiency Groups at greatest risk for deficiency Vegetarians Zinc Snapshot Fluoride Not essential to life Roles in the body Roles in the body Deficiency Dental decay Toxicity Fluorosis Sources U.S. Population with Access to Fluoridated Water Through Public Water Systems Food Sources of Calcium in the U.S. Diet Calcium Absorption from Food Sources