The Fat-Soluble Vitamins A, D, E, and K The Fat-Soluble Vitamins Vitamin A And Beta-Carotene • Retinoids and carotenoids –Vitamin A activity Vitamin A And Beta-Carotene Vitamin A And Beta-Carotene • Retinol-binding protein (RBP) Vitamin A And Beta-Carotene • Roles in the body –Vitamin A in vision • Roles in the body –Vitamin A in protein synthesis and cell differentiation Vitamin A And Beta-Carotene • Roles in the body –Vitamin A in reproduction and growth –Beta-carotene as an antioxidant Vitamin A And Beta-Carotene • Recommendations –Retinol activity equivalents (RAE) Vitamin A And Beta-Carotene • Vitamin A in foods –The colors of vitamin A foods –Vitamin A-poor fast foods –Vitamin A-rich liver In Summary • Other names –Retinol –Retinal –Retinoic acid –Precursors are carotenoids such as beta-carotene • 2001 RDA –Men: 900 g RAE/day –Women: 700 g RAE/day In Summary • Upper level for adults: 3000 g/day • Chief functions in the body –Vision –Maintenance of cornea, epithelial cells, mucous membranes, skin –Bone and tooth growth –Reproduction –Immunity In Summary • Significant sources –Retinol: fortified milk, cheese, cream, butter, fortified margarine, eggs, liver –Beta-carotene: spinach and other dark leafy greens; broccoli, deep orange fruits (apricots, cantaloupe) and vegetables (squash, carrots, sweet potatoes, pumpkin) In Summary • Deficiency disease: hypovitaminosis A • Deficiency symptoms –Night blindness, corneal drying (xerosis), triangular gray spots on eye (Bitot’s spots), softening of the cornea (keratomalacia), and corneal degeneration and blindness (xerophthalmia) In Summary • Deficiency symptoms (continued) –Impaired immunity (infections) –Plugging of hair follicles with keratin, forming white lumps (hyperkeratosis) Deficiency Symptom: Keratinization In Summary • Toxicity disease: hypervitaminosis A • Chronic toxicity symptoms –Increased activity of osteoclasts causing reduced bone density –Liver abnormalities –Birth defects In Summary • Acute toxicity symptoms –Blurred vision –Nausea, vomiting, vertigo –Increase of pressure inside skull, mimicking brain tumor –Headaches Vitamin D • Other names –Calciferol –1,25-dihydroxy vitamin D (calcitriol) –Animal version: vitamin D3 or cholecalciferol –Plant version: vitamin D2 or ergocalciferol –Precursor is the body’s own cholesterol Vitamin D • 1997 adequate intake (AI) –19-50 years: 5 g/day –51-70 years: 10 g/day –more than 70 years: 15 g/day • Upper level for adults: 50 g/day Vitamin D • Chief functions in the body –Mineralization of bones (raises blood calcium and phosphorus by increasing absorption from digestive tract, withdrawing calcium from bones, stimulating retention by kidneys) Vitamin D • Significant sources –Synthesized in the body with the help of sunlight –Fortified milk, margarine, butter, cereals, and chocolate mixes –Veal, beef, egg yolks, liver, fatty fish (herring, salmon, sardines) and their oils Vitamin D • Deficiency diseases –Rickets –Osteomalacia Vitamin D • Deficiency symptoms: rickets in children –Inadequate calcification, resulting in misshapen bones (bowing of legs) –Enlargement of ends of long bones (knees, wrists) –Deformities of ribs (bowed, with beads or knobs) Vitamin D • Deficiency symptoms: rickets in children (continued) –Delayed closing of fontanel, resulting in rapid enlargement of head Vitamin D • Deficiency symptoms: rickets in children (continued) –Lax muscles resulting in protrusion of abdomen –Muscle spasms • Deficiency symptoms: osteomalacia in adults –Loss of calcium, resulting in soft, flexible, brittle, and deformed bones Vitamin D • Deficiency symptoms: osteomalacia in adults (cont.) –Progressive weakness –Pain in pelvis, lower back, and legs • Toxicity disease: hypervitaminosis D Vitamin D • Toxicity symptoms –Elevated blood calcium –Calcification of soft tissues (blood vessels, kidneys, heart, lungs, tissues around joints) –Frequent urination Vitamin E • Other name: alpha-tocopherol • 2000 RDA – Adults: 15 mg/day • Upper level for adults: 1000 mg/day • Chief function in the body – Antioxidant (stabilization of cell membranes, regulation of oxidation reactions, protection of polyunsaturated fatty acids and vitamin A) Vitamin E Vitamin E • Significant sources –Polyunsaturated plant oils (margarine, salad dressings, shortenings) –Leafy green vegetables, wheat germ, whole grains, liver, egg yolks, nuts, seeds Vitamin E • Easily destroyed by heat and oxygen • Deficiency symptoms –Red blood cell breakage –Nerve damage • Toxicity symptoms –Augments the effects of anticlotting medication Vitamin K • Other names –Phylloquinone –Menaquinone –Menadione –Naphthoquinone • 2001 AI –Men: 120 g/day –Women: 90 g/day Vitamin K • Chief functions in the body –Synthesis of blood-clotting proteins and bone proteins that regulate blood calcium Vitamin K • Significant sources –Bacterial synthesis in the digestive tract –Liver –Leafy green vegetables, cabbage-type vegetables –Milk Vitamin K • Deficiency symptoms –Hemorrhaging • Toxicity symptoms –None known The Fat-Soluble Vitamins In Summary • Interactions with each other • Interactions with minerals Antioxidant Nutrients In Disease Prevention • Free radicals and disease –Oxidative stress • Defending against free radicals –Oxidants and antioxidants Antioxidant Nutrients In Disease Prevention Antioxidant Nutrients In Disease Prevention • Defending against cancer • Defending against cardiovascular disease Antioxidant Nutrients In Disease Prevention • Foods, supplements, or both? –Prooxidants Water And The Major Minerals Water And The Body Fluids • Functions of water: –Transport –Structural support for molecules –Participates in metabolic reactions –Solvent –Lubricant –Body temperature regulation –Maintains blood volume Water And The Body Fluids • Water balance and recommended intakes –Intracellular fluid –Extracellular fluid •Interstitial fluid One Cell And Its Associated Fluids Water And The Body Fluids • Water balance and recommended intakes –Water intake •Dehydration •Water intoxication Water And The Body Fluids • Water balance and recommended intakes –Water sources –Water losses –Water recommendations • Water balance and recommended intakes –Health effects of water •Hard water vs. soft water •Bottled water How The Body Regulates Blood Volume Fluid And Electrolyte Balance • Dissociation of salt in water –Ions •Cations •Anions –Electrolyte solution Water Dissolves Salts And Follows Electrolytes Fluid And Electrolyte Balance • Electrolytes attract water • Water follows electrolytes –Solutes –Osmosis –Osmotic pressure • Vegetables “sweat” when sprinkled with salt • Raisins plump up when immersed in water Fluid And Electrolyte Balance • Proteins regulate flow of fluids and ions • Regulation of fluid and electrolyte balance Fluid And Electrolyte Imbalance • Sodium and chloride most easily lost • Different solutes lost by different routes Fluid And Electrolyte Imbalance • Replacing lost fluids and electrolytes –Oral rehydration therapy (ORT) Acid-Base Balance • pH Acid-Base Balance • Regulation by the buffers –Bicarbonate –Carbonic acid • Regulation by the lungs • Regulation by the kidneys The Minerals An Overview The Minerals An Overview • Inorganic elements • The body’s handling of minerals The Minerals An Overview • Variable bioavailability –Binders •Phytates •Oxalates The Minerals An Overview • Nutrient interactions • Varied roles Sodium • Roles in the body –Principal extracellular cation Sodium • Hypertension –Salt sensitivity • Osteoporosis • Foods Sodium Sodium: In Summary • 1989 estimated minimum requirement for adults: 500 mg/day • Chief functions in the body – Maintains normal fluid and electrolyte balance – Assists in nerve impulse transmission and muscle contraction Sodium: In Summary • Deficiency symptoms – Muscle cramps, mental apathy, loss of appetite • Toxicity symptoms – Edema, acute hypertension • Significant source – Table salt, soy sauce – Moderate amounts in meats, milks, breads, and vegetables – Large amounts in processed foods Chloride • Chlorine (Cl2) vs. chloride ion (Cl-) • Roles in body –Principal extracellular anion Chloride: In Summary • 1989 estimated minimum requirement for adults: 750 mg/day • Chief functions in the body – Maintains normal fluid and electrolyte balance – Part of hydrochloric acid found in the stomach, necessary for proper digestion Chloride: In Summary • Deficiency symptoms – Do not occur under normal circumstances • Toxicity symptom – Vomiting • Significant sources – Table salt, soy sauce – Moderate amounts in meats, milks, eggs – Large amounts in processed foods Potassium • Principal intracellular cation Potassium: In Summary • 1989 estimated minimum requirement for adults: 2000 mg/day • Chief functions in the body – Maintains normal fluid and electrolyte balance – Facilitates many reactions – Supports cell integrity – Assists in nerve impulse transmission and muscle contractions Potassium: In Summary • Deficiency symptoms – Muscular weakness – Paralysis – Confusion • Toxicity symptoms – Muscular weakness – Vomiting – If given into a vein, can stop the heart Potassium: In Summary • Significant sources – All whole foods – Meats, milks, fruits, vegetables, grains, legumes Calcium Balance Calcium • Calcium rigor vs. calcium tetany Calcium Calcium: In Summary • 1997 adequate intake (AI) –Adults 19-50 years: 100 mg/day –Adults 51 and older: 1200 mg/day • Upper level for adults: 2500 mg/day Calcium: In Summary • Chief functions in the body –Mineralization of bones and teeth –Involved in muscle contraction and relaxation, nerve functioning, blood clotting –Blood pressure, immune defenses Calcium: In Summary • Deficiency symptoms –Stunted growth in children –Bone loss (osteoporosis) in adults Calcium: In Summary • Toxicity symptoms –Constipation –Increased risk of urinary stone formation and kidney dysfunction –Interference with absorption of other minerals Calcium: In Summary • Significant sources –Milk and milk products –Small fish (with bones) –Tofu (bean curd), greens (broccoli, chard), legumes Phosphorus • 1997 RDA for adults: 700 mg/day • Upper level for adults (19-70 years): 4000 mg/day • Chief functions in the body –Mineralization of bones and teeth –Part of every cell –Important in genetic material, part of phospholipids Phosphorus • Chief functions in the body (continued) –Used in energy transfer and in buffer systems that maintain acid-base balance • Deficiency symptoms –Muscular weakness, bone pain Phosphorus • Toxicity symptoms –Calcification of nonskeletal tissues, particularly the kidneys • Significant sources –All animal tissues (meat, fish, poultry, eggs, milk) Magnesium • 1997 RDA – Men (19-30 years): 400 mg/day – Women (19-30 years): 310 mg/day • Upper level for adults: 350 mg nonfood magnesium/day • Chief functions in the body – Bone mineralization, building of protein, enzyme action, normal muscle contraction, nerve impulse transmission, maintenance of teeth, and functioning of immune system Magnesium • Deficiency symptoms – Weakness – Confusion – If extreme, convulsions, bizarre muscle movements (especially of eye and face muscles), hallucinations, and difficulty in swallowing – In children, growth failure Magnesium • Toxicity symptoms – From nonfood sources only – Diarrhea, alkalosis, dehydration • Significant sources – Nuts, legumes – Whole grains – Dark green vegetables – Seafood – Chocolate, cocoa Sulfur • Roles Osteoporosis And Calcium • Bone development and disintegration –Cortical bone –Trabecular bone Healthy vs. Osteoporotic Trabecular Bones Osteoporosis And Calcium • Bone development and disintegration –Bone density Osteoporosis And Calcium • Age and bone calcium • Maximizing bone mass Osteoporosis And Calcium Osteoporosis And Calcium • Minimizing bone loss • Gender and hormones • Genetics and ethnicity Osteoporosis And Calcium • Physical activity and body weight • Smoking and alcohol Osteoporosis And Calcium • Dietary calcium is the key to prevention • Other nutrients play a supporting role Osteoporosis And Calcium Osteoporosis And Calcium Osteoporosis And Calcium • A perspective on supplements –Antacids –Bone meal –Oyster shell –Dolomite (limestone) The Trace Minerals The Trace Minerals The Trace Minerals • Food sources • Deficiencies • Toxicities • Interactions Iron • Ferrous (Fe++) –Reduced • Ferric (Fe+++) –Oxidized Iron Absorption Iron: Heme vs. Nonheme Iron • Factors enhance nonheme iron absorption –MFP factor –Vitamin C –Citric acid from foods Iron • Factors enhance nonheme iron absorption –Lactic acid from foods –HCl from stomach –Sugars Iron • Factors inhibit nonheme iron absorption –Phytates –Fibers –Oxalates Iron • Factors inhibit nonheme iron absorption –Calcium –Phosphorus –EDTA –Tannic acid Iron Recycling Iron • High risk for iron deficiency –Women in their reproductive years –pregnant women –Infants and young children –Teenagers Iron • Stages of iron deficiency –Iron stores diminish –Transport iron decreases –Hemoglobin production declines • Both size and color are normal in these blood cells • Blood cells in iron-deficiency anemia are small and pale because they contain less hemoglobin Iron • Contamination iron • Iron supplements Iron: In Summary • 2001 RDA – Men: 8 mg/day – Women (19-50 years): 18 mg/day – Women (51+ years): 8 mg/day • Upper level for adults: 45 mg/day Iron: In Summary • Chief functions in the body – Part of the protein hemoglobin, which carries oxygen in the blood – Part of the protein myoglobin in muscles, which makes oxygen available for muscle contraction – Necessary for the utilization of energy as part of the cells’ metabolic machinery Iron: In Summary • Significant sources – Red meats, fish, poultry, shellfish, eggs – Legumes, dried fruits Iron: In Summary • Deficiency symptoms – Anemia: weakness, fatigue, headaches – Impaired work performance and cognitive function – Impaired immunity – Pale skin, nailbeds, mucous membranes, and palm creases – Concave nails – Inability to regulate body temperature – Pica Iron: In Summary • Toxicity symptoms – GI distress – Iron overload: infections, fatigue, joint pain, skin pigmentation, organ damage Zinc • Roles –Metalloenzymes • Absorption –Metallothionein Zinc • Enteropancreatic circulation Zinc • Zinc supplementation Zinc: In Summary • 2001 RDA – Men: 11 mg/day – Women: 8 mg/day • Upper level for adults: 40 mg/day Zinc: In Summary Chief functions in the body – Part of many enzymes – Associated with the hormone insulin – Involved in making genetic material and proteins, immune reactions, transport of vitamin A, taste perception, wound healing, the making of sperm, and the normal development of the fetus Zinc • Significant sources – Proteincontaining foods – Red meats, shellfish – Whole grains Zinc • Deficiency symptoms – Growth retardation, delayed sexual maturation, impaired immune function, hair loss, eye and skin lesions, loss of appetite Zinc: In Summary • Toxicity symptoms – Loss of appetite, impaired immunity, low HDL, copper and iron deficiencies Iodine • Iodine vs. iodide • Deficiency –Goitrogens Iodine: In Summary • 2001 RDA for adults: 150 g/day • Upper level: 1100 g/day • Chief functions in the body – A component of two thyroid hormones that help to regulate growth, development, and metabolic rate Iodine: In Summary • Significant sources – Iodized salt, seafood, bread, dairy products, plants grown in iodine-rich soil and animals fed those plants • Deficiency disease – Simple goiter – Cretinism Iodine: In Summary • Deficiency symptoms – Underactive thyroid gland, goiter – Mental and physical retardation in infants (cretinism) • Toxicity symptoms – Underactive thyroid gland, elevated TSH, goiter Selenium • 2000 RDA for adults: 55 g/day • Upper level for adults: 400 g/day • Chief functions in the body – Defends against oxidation – Regulates thyroid hormone • Significant sources – Seafood, meat – Whole grains, vegetables (depending on soil content) Selenium • Deficiency symptoms – Predisposition to heart disease characterized by cardiac tissue becoming fibrous (Keshan disease) • Toxicity symptoms – Loss and brittleness of hair and nails – Skin rash, fatigue, irritability, and nervous system disorders – Garlic breath odor Copper • 2001 RDA for adults: 900 g/day • Upper level for adults: 10,000 g/day (10 mg/day) • Chief functions in the body – Necessary for absorption and use of iron in the formation of hemoglobin – Part of several enzymes Copper • Significant sources – Seafood – Nuts, whole grains, seeds, legumes • Deficiency symptoms – Anemia, bone abnormalities • Toxicity symptoms – Liver damage Manganese • 2001 AI – Men: 2.3 mg/day – Women: 1.8 mg/day • Upper level for adults: 11 mg/day • Chief functions in the body – Cofactor for several enzymes Manganese • Significant sources – Nuts, whole grains, leafy vegetables, tea • Deficiency symptoms – Rare • Toxicity symptoms – Nervous system disorders Fluoride • 1997 AI – Men: 3.8 mg/day – Women: 3.1 mg/day • Upper level for adults: 10 mg/day • Chief functions in the body – Involved in the formation of bones and teeth – Helps to make teeth resistant to decay U.S. Population With Fluoridated Water Fluoride • Significant sources – Drinking water (if fluoride containing or fluoridated) – Tea, seafood • Deficiency symptoms – Susceptibility to tooth decay • Toxicity symptoms – Fluorosis (pitting and discoloration of teeth) Chromium • 2001 AI – Men: 35 g/day – Women: 25 g/day • Chief functions in the body – Enhances insulin action • Significant sources – Meats (especially liver) – Whole grains, brewer’s yeast Chromium • Deficiency symptoms – Diabetes-like condition • Toxicity symptoms – None reported Molybdenum • 2001 AI for adults: 45 g/day • Upper level for adults: 2 mg/day • Chief functions in the body – Cofactor for several enzymes • Significant sources – Legumes, cereals – Organ meats Molybdenum • Deficiency symptoms – Unknown • Toxicity symptoms – None reported – Reproductive effects in animals Other Trace Minerals • Nickel • Silicon • Vanadium Other Trace Minerals • Cobalt • Boron • Arsenic Contaminant Minerals • Heavy metals –Lead Phytochemicals And Functional Foods Phytochemicals And Functional Foods Phytochemicals And Functional Foods • Defending against cancer • Defending against heart disease • Functional foods... – from nature – from manufacturers Phytochemicals And Functional Foods Functional foods – Inconclusive research – Food labels – Safety – Overall healthfulness of products