Trace Minerals PDF

The Trace Minerals 1  Iron Forms – Ferrous (Fe++) – reduced form – Ferric (Fe+++) – oxidized form Roles in the Body Cofactor in oxidation-reduction reactions Part of the protein hemoglobin which ca...

The Trace Minerals 1  Iron Forms – Ferrous (Fe++) – reduced form – Ferric (Fe+++) – oxidized form Roles in the Body Cofactor in oxidation-reduction reactions Part of the protein hemoglobin which carries oxygen in the blood Part of the protein myoglobin in the muscles which makes oxygen available for muscle contractions Utilization of energy in cell metabolism 2 Iron Absorption 3  Iron Iron occurs in two forms in food : heme iron: animal source nonheme iron: animal and plant sources Heme iron has a high bioavailability and is not influenced by dietary factors. Factors enhance nonheme iron absorption – MFP factor (peptide release during meat, fish and poultry digestion), Vitamin C, Citric acid, Lactic acid from foods, HCl from stomach, Sugars Factors inhibit nonheme iron absorption – Phytates, Fibers, Oxalates, Calcium and Phosphorus in milk, Tannic acid, EDTA (Ethylenediaminetetraacetic acid). 4  Iron Absorption Iron: Heme vs. Nonheme 5 Iron Transport and Recycling 6  Iron Significant sources – Red meats, fish, poultry, shellfish, eggs – Legumes, dried fruits RDA – Men: 8 mg/day – Women (19-50 years): 18 mg/day – Women (51+ years): 8 mg/day High risk for iron deficiency – Women in their reproductive years – pregnant women – Infants and young children – Teenagers 7 Stages of iron deficiency and assessment tools Stages of iron deficiency Assessment of Iron Deficiency Stage 1: Iron stores diminish measure serum ferritin Stage 2: Transport iron decreases measure transferrin saturation Stage 3: Hemoglobin production Hemoglobin and hematocrit declines tests 8  Iron Iron Deficiency and Anemia – Iron deficiency is depleted iron stores. – Iron-deficiency anemia is the severe depletion of iron stores. Also called microcytic hypochromic anemia. – Symptoms include fatigue, weakness, headaches, apathy, pallor and poor resistance to cold temperatures. Iron Deficiency and Behavior – Energy metabolism is impaired. – Neurotransmitter synthesis is reduced. – Physical work capacity is reduced. – Mental productivity is reduced. Iron Deficiency and Pica – Habit of eating ice, clay, paste, and other nonfood substances – Generally in women and children from low-income groups 9  Iron Iron Toxicity – Iron Overload Known as Hemochromatosis, is usually caused by a genetic disorder that enhances iron absorption. Repeated blood transfusions Massive doses of supplemental iron May cause hemosiderosis Symptoms include apathy, lethargy, and fatigue 10  Zinc Roles in the Body Supports the work of metalloenzymes – Helps to make parts of DNA and RNA – Manufactures heme for hemoglobin – Assists in essential fatty acid metabolism – Releases Vitamin A from liver stores – Metabolizes carbohydrates – Synthesizes proteins Affects platelets in blood clotting and wound healing Affects thyroid hormone function Influences behavior and learning performance Taste perception Sperm development Fetal development Zinc Absorption Rate of absorption depends on zinc status Phytates and fiber bind zinc and reduce absorption. 11  Zinc Significant sources – Protein-containing foods – Red meats, shellfish – Whole grains RDA – Men: 11 mg/day – Women: 8 mg/day Deficiency symptoms – Growth retardation, delayed sexual maturation, impaired immune function, hair loss, eye and skin lesions, loss of appetite Toxicity symptoms – Loss of appetite, impaired immunity, copper and iron deficiencies 12  Iodine – Iodide Roles in the Body Component of two thyroid hormones Regulates growth, development, and metabolic rate – Iodine Deficiency Simple goiter is the enlargement of the thyroid gland caused by iodine deficiency. Goiter is enlargement of the thyroid gland due to malfunction of the gland, iodine deficiency or overconsumption of goitrogens. Cretinism is a congenital disease characterized by mental and physical retardation and commonly caused by maternal iodine deficiency during pregnancy. – Iodine Toxicity Symptoms include underactive thyroid gland and goiter. - RDA for adults: 150 g/day - Sources: Iodized salt, Seafood, Bread and dairy products, Plants grown in iodine-rich soils, Animals that feed on plants grown in iodine- rich soils 13  Other Trace Minerals Copper - Roles in the Body Part of several enzymes Some copper containing enzymes are antioxidants. - Deficiency Deficiency symptoms include anemia and bone abnormalities. Menkes disease - Toxicity – Wilson’s disease - RDA for adults: 900 g/day - Sources: Seafood, nuts, seeds, legumes and Whole grains 14  Other Trace Minerals Fluoride – Roles in the Body Formation of teeth and bones Helps to make teeth resistant to decay – Deficiency: tooth decay – Toxicity: Tooth damage called fluorosis – AI Men: 4 mg/day Women: 3 mg/day - Sources: Fluoridated drinking water,Seafood, tea Chromium – Roles in the Body Enhances insulin action: Glucose tolerance factors (GTF) are small organic compounds that enhance insulin’s action AI Men: 35 g/day AI Women: 25 g/day Sources: Meat, liver, Whole grains, Brewer’s yeast 15  Contaminant Minerals Contaminate minerals are also called heavy metals. These include mercury, lead, and cadmium. These minerals enter the food supply through soil, water, and air pollution. They disrupt body processes and impair nutrition status. 16