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The Trace Minerals Objectives • After reading Chapter and class discussion, you will be able to: – – – – Identify trace minerals Define trace minerals Define hemoglobin and myoglobin Describe heme and nonheme iron and its absorption Objectives • Identify food sources of iron • Identify those at high risk for iron deficiency • Identify recommendation for daily iron intake • Describe iron toxicity symptoms The Trace Minerals The Trace Minerals • Other Trace Minerals – Chromium – Molybdenum – Manganese -Selenium -Nickel -Silicon • IRON – – – – – Functions Absorption Deficiency/Toxicity Recommendations Food sources -Fluoride -Copper -Cobalt Iron: Functions • 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 Absorption Iron: Heme vs Nonheme Factors Enhancing Nonheme Iron Absorption • MFP factor • Vitamin C • Citric acid from foods & stomach • Lactic acid from foods • HCl from stomach • Sugars (including wine) Factors Inhibiting Nonheme Iron Absorption • Phytates – soy products • Fibers – whole grains, nuts • Oxalates – spinach, beets, rhubarb • Calcium • Phosphorus • EDTA (food additive, preservative) • Tanic acid – tea, coffee Toxicity Symptoms • GI distress • Iron overload: infections, fatigue, joint pain, skin pigmentation, organ damage Recommendations • 2001 RDA – Men: mg/day – Women (19-50 years): 18 mg/day – Women (51+ years): mg/day • Upper level for adults: 45 mg/day Iron: Food Sources • Significant sources – Red meats, fish, poultry, shellfish, eggs – Legumes, dried fruits – Enrichment Non-Food Sources of Iron • Contamination iron from iron cookware – More acidic the food – Longer cooking time – Fe content of eggs can triple – Poorly absorbed • 1-2% absorbed Iron Supplements • Form – Ferrous sulfate or iron chelate – Less well absorbed so doses high • Take between meals or bedtime • Take on empty stomach • Take with liquids – Not milk, tea, coffee • Take as a single dose More On Supplements • No benefit to taking supplements with orange juice (Vitamin C) – Vitamin C converts insoluble ferric iron in foods to more soluble form of ferrous iron • Constipation a common side effect of iron supplementation – Increase water intake – Is there a negative impact to increasing fiber intake? Objectives • After reading Chapter and class discussion, you will be able to: – – – – Identify trace minerals Define trace minerals Define hemoglobin and myoglobin Describe heme and nonheme iron and its absorption Objectives • Identify food sources of iron • Identify those at high risk for iron deficiency • Estimate recommendation for daily iron intake • Describe iron toxicity symptoms [...]... common side effect of iron supplementation – Increase water intake – Is there a negative impact to increasing fiber intake? Objectives • After reading Chapter 7 and class discussion, you will be able to: – – – – Identify trace minerals Define trace minerals Define hemoglobin and myoglobin Describe heme and nonheme iron and its absorption Objectives • Identify food sources of iron • Identify those at high