Chapter 11 12 Flashcards
(52 cards)
classifying minerals
- essential
- need small amounts
- major and trace minerals
understanding minerls
- inorganic (no c)
- involved in body structure and regulation
found in plant and animal foods - not destroyed by extreme conditions
calcium - bone
- synthesis and maintemance
- constant turnover (bone formation and resorption)
- storage place for calcium
importance of calcium and vit d
- prevent osteoporosis
- youth and adolescent intake is critical
osteoporosis
- bones break with low energy
- poor bone density and structure
- due to lack of bone accrual during growth or bone loss with age or meds
nutrients that benefit bone health
- calcium - hydroxyapatite formation
- vitamin d - preserves Ca
- protein - important for strong collagen
- magnesium and vit K
calcium functions
- bone structure
- blood clotting
- nerve impulse transmission
- muscle contraction
calcium regulations
- homeostatic control in blood
- hypocalcemia results in raiding bone for Ca
regulation of blood calcium
- high blood calcium: thyroid gland –> calcitonin –> inhibits calcium release from bone –> normal
- low blood calcium: parathyroid gland –> parathyroid hormone –> stimulates calcium release by bone, calcium reabsorbed by kidney, activates vit d –> increases intestinal calcium absorption –> normal
calcium dri
- adolescent: 1300mg
- adults <50: 1000mg
- adults >51: 1200mg
fractional ca absorption
- inversely proportional to Ca status
- if you have good Ca you will absorb less
factors that increase risk of low bone strength
- high sodium intake
- phytate (interferes w absorption)
- oxalate (interferes with absorption)
- fluoride
food sources of calcium
- milk and dairy
- fortified foods
- fish bones
- green veg
- tofu
- supplements
calcium requirements are controversial
- is loading through exercise more important
- does harm occur if a growing teen consumes less than 1300mg per day
- if youre loading your bones is a low Ca diet ok
- high impact moves good
magnesium
- part of reactions: cardiac function, enegy metabolism
- stored in bone
- 50% consumed absorbed
- high in plant based foods
magnesium deficiency
- causes: intake, dieting, high meat low veg
- malabsorption
- excessive excretion
- hard to detect bc mg is in bone
- method of detection: serum magnesium
- low serium levels have little correlation with total mg levels
iron
- oxygen transport: heme part of hemoglobin and myogloin
- cofactor for enzymes
- needed for normal brain
- needed for immune function
iron food sources
- red meat
- liver
- seafood
iron deficiency
- causes anemia; fatigue
- babies: milk low in Fe
- blood loss, parasites, poor absorption, low intake
iron absorption
- absorb 1-50%
- usually absorb 5-15%
- absrob more with vitc and less with Ca
- aging: stomach acid decreases so need more fe
iron toxicity
- children: due to poisoning
- adults: hemochromatosis - hereditary, liver disease, blood letting reduces toxic fe
iron deficency and dental caries
- iron supplements reduce dental caries in rats
- fe deficiency: saliva promotes colonization of s mutans
- low serum iron in kids with high early childhood dental caries
zinc functions
- cofactor for enzymes
- gene regulation
- immune health
zinc food sources
- red meats, seafood