300 likes | 511 Views
The Trace Minerals. 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
E N D
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 risk for iron deficiency • Identify recommendation for daily iron intake • Describe iron toxicity symptoms
The Trace Minerals • Other Trace Minerals • Chromium -Selenium -Fluoride • Molybdenum -Nickel -Copper • Manganese -Silicon -Cobalt • IRON • Functions • Absorption • Deficiency/Toxicity • Recommendations • Food sources
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
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
Iron Deficiency • High risk for iron deficiency • Women in reproductive years • Pregnant women • Infants and young children • Teenagers • Blood loss
Iron Deficiency • How is Fe deficiency measured? • How does Fe deficiency develop? • Stages of iron deficiency • Iron stores diminish • Transport iron decreases • Hemoglobin production declines
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
Toxicity Symptoms • GI distress • Iron overload: infections, fatigue, joint pain, skin pigmentation, organ damage
Recommendations • 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: 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 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 risk for iron deficiency • Estimate recommendation for daily iron intake • Describe iron toxicity symptoms