Transcript Trace Minerals - lbccnutrition

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: 12-17 mg/day
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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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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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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
http://www.chop.edu/service/poison-controlcenter/tox-talk/iron-poisoning.html
– Hemochromatosis
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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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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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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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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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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 190-300 micrograms
• Absorption, Transportation, Storage, and
Excretion
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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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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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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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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
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Chromium (2)
• Functions
– May enhance insulin function
• Deficiency and Toxicity
– Not well established
– No UL
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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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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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Molybdenum and Ultra Trace
Minerals
• Molybdenum
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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
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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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Genetic, Environmental, and
Dietary Factors
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Fruits and vegetables
Excessive energy intake and obesity
Meat
Fried Foods
Alcohol
Vitamin D and calcium
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