1 Iron Foods –Heme iron –Non-heme iron –Meats, seafoods and enriched bakery products Needs –RDA: 18 mg/day adult women, 8 mg/day adult men After menopause drops to 8 mg/day –Average North American intake: mg/day

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3 Iron (2) Absorption, Transportation, Storage, and Excretion –Ferritin, Transferrin, Lysosomes –Hemosiderin –Bile Factors Affecting Iron Absorption –Body’s iron needs and stores –Form of iron in foods eaten, and total amount consumed –Dietary composition and gastric contents acidity –Factors that hinder non-heme absorption

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6 Functions of Iron Part of Hemoglobin and Myoglobin Iron-containing enzymes –Energy metabolism, mitochondrial cytochromes, –Drug metabolism in liver Enzyme co-factor –Production of immune system components

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8 Iron Deficiency, Overload, and Toxicity Def –Most widespread mineral deficiency worldwide –Iron deficiency anemia –At risk: premature infants, children, females of childbearing age, vegetarians Overload and toxicity –UL: 45 mg/day –Accidental overdose in children center/tox-talk/iron-poisoning.html center/tox-talk/iron-poisoning.html –Hemochromatosis

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11 Zinc Foods –Protein-rich meat and seafood’ also nuts, beans, and whole grains Effect of phytic acid in whole grains Needs –RDA: 11mg/d adult men, 8 mg/d adult women –DV: 15 mg Absorption, Transportation, Storage, and Excretion –metallothionein

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14 Zinc (2) Functions –As many as 300 different enzymes require zinc DNA and RNA synthesis, heme synthesis, bone formation, taste acuity, immune function, reproduction, growth, etc. Deficiency –Overt deficiency common when poverty limits food choices –North America: mild or marginal deficiencies Toxicity –UL: 40 mg/day

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16 Copper Foods –Liver, shellfish, nuts, seeds, lentils, soy and dark chocolate Functions –Component of enzymes –Superoxide dismutase enzymes Toxicity –Wilson’s disease –UL:10 mg/day

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18 Manganese Foods - Whole-grain cereals, nuts, legumes, leafy greens, and tea Functions –Shares functional similarities with Zinc and Copper –Carbohydrate metabolism, gluconeogenesis, collagen formation, antioxidant system, etc. Deficiency –rare

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20 Iodine Foods –Saltwater seafood, seaweed, iodized salt, and dairy products –Goitrogens decrease bioavailability of iodine and inhibit use by thyroid gland Needs –RDA and DV: 150 micrograms/d –Average intake micrograms Absorption, Transportation, Storage, and Excretion

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22 Iodine (2) Functions –Component of thryoxine (T4) and triodothyronine (T3) Deficiency –Iodine Deficiency Disorders (IDD) Endemic goiter Endemic cretenism Toxicity –UL: 100 micrograms/d –Enlarged thyroid gland

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24 Selenium Foods –Dependent on soil content –Seafood, meats, cereal, and grains Needs –RDA: 55 micrograms adults –DV: 70 micrograms Absorption, Transportation, Storage, and Excretion

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26 Selenium (2) Functions –Antioxidant defense network Glutathione peroxidase –Thyroid metabolism, immune function, etc. Deficiency –Not established –Associated with Keshan disease Toxicity –UL: 400 micrograms/d

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28 Chromium Foods –Nutrient databases inadequate –Processed meats, liver, eggs, whole grain products, broccoli, dried beans, nuts, dark chocolate Needs –AI: 35 micrograms men up to age 50, then 30 micrograms; 25 micrograms women up to age 50, then 20 micrograms –DV: 120 micrograms Absorption, Transportation, Storage, and Excretion

29 Chromium (2) Functions –May enhance insulin function Deficiency and Toxicity –Not well established –No UL

30 Fluoride Foods –Fluoridated water, tea, seafood, and seaweed Needs –AI: 3 mg/d adult women, 4 mg/d adult men Absorption, Transportation, Storage, and Excretion

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32 Fluoride (2) Functions –Deposition of Ca and P in teeth and bones Promotes bone and dental health Deficiency –Associated with an increase in dental caries Toxicity –UL: 0.1 mg/kg body weight/d up to 8 years old, 10 mg/d over 8 years old –Mottling (fluorosis)

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34 Molybdenum and Ultra Trace Minerals Molybdenum –Dietary sources: plant-based foods; soil dependent –RDA: 45 micrograms/d; DV: 75 micrograms/d –Functions: cofactor in enzymatic reactions –UL: 2000 micrograms/d Nickel, Vanadium, Boron, Silicon, and Arsenic

35 Nutrients, Diet, and Cancer What is cancer? –Benign and malignant tumors –Tumors can metastasize Development of cancer –Protooncogenes and oncogenes –Carcinogenesis Step 1: Exposure of the cell to carcinogen Step 2: Promotion state Step 3: Cancer progression

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37 Genetic, Environmental, and Dietary Factors Fruits and vegetables Excessive energy intake and obesity Meat Fried Foods Alcohol Vitamin D and calcium

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