NUTR 202 1nd Edition Lecture 16 Ch 8 Continued Calcium absorption in GI depends on the availability of Vitamin D Parathyroid Hormone PTH Absorption also higher when needs are higher Bioavailability of calcium is decreased in the presence of certain substances in foods Tannins fiber phytates and oxalates Minerals w same charge Fe Bioavailability of Ca is increased in pregnant women Ca is the most abundant mineral in the body RDA 19 50 years 1000 mg day UL 2500 mg day Sources dairy products dark green vegetables fish with bones foods processed and fortified with calcium 99 of calcium in the body is found in solid mineral deposits in the bones and teeth Will be at risk if Ca in 1 is not enough Provides structure for bones Also found in teeth The remaining 1 is found in intracellular fluid blood and extracellular fluid for Release of hormones Nerve transmission Muscle contraction Normal BP regulation Decreased blood calcium Calcitonin These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute PTH Stimulates intestinal absorption kidney reabsorption bone resorption Increased blood calcium At risk is Ca in the bones PTH active vitamin D be able to absorb more Ca in small intestine Rel from bone Too much or too little UL 2 500 mg day Too much calcium Hypercalcemia usually from supplements too much in bldstream May impaired kidney function Calcium deposits in body Risk of calcium stones Constipation may interfere with absorption of certain minerals iron zinc magnesium and phosphorus Remember bioavailability minerals with same charge will compete to be absorbed Osteopenia is Reduced bone density below normal levels Osteoporosis The bone disorder characterized by reduced bone mass increased bone fragility and increased risk of factures Osteoporosis is the most common bone disease 10 million Americans have osteoporosis 55 Osteoporosis lead to 1 5 million fractures annually which account for 18 billion per year in medical costs By 2025 experts predict that these costs will rise to 25 3 billion More common in women increases with age AA have DENSER bones if thin you are at risk lack of exercise or diet low in Ca Vitamin D and high in Phosphorous Ex a 65 year old woman who is thin and drinks alcohol will be at a greater risk than an overweight male AA female who jogs 20 year old male who plays football Phosphorous Second most abundant mineral in body need less than Ca in bone Most located in bones 85 hard mineral in bones teeth Remainder in cells and fluids outside cells including blood Fxn E metabolism ATP is made of 3 PHOSPHATE groups PHOSPHOlipids acid base balance enzyme activity inactive active need P and DNA RNA contain P Daily needs Adults 700 mg day Food sources Meat fish poultry dairy food additives i e sodas abundant in diet Can lead to poor bone density bc reduce amt of Ca in bld Excess Phosphorus intake Calcification deposit in tissues Associated with poor bone density UL set at 4 000 mg day for adults 19 50 Phosphorus deficiency rare Muscle weakness bone loss loss of appetite Trace Minerals Iron zinc copper manganese selenium iodine fluoride chromium and molybdenum They are required in an amount less than 100 mg per day Trace minerals have been difficult to study as they are difficult to remove from the diet Absorption may be affected by bioavailability Fluoride Functions Protects against dental caries Fluoridated drinking water has reduced dental caries in U S Associated with bone health Daily needs Men 3 8 mg day women 3 1 mg day Sources Fluoridated drinking water foods are not a good source Tea bones of marine fish toothpaste Too much Fluorosis mottling staining during infancy childhood UL adults 10 mg day much lower for infants and children Too little Too little increases risk of dental caries Less than 1mg L Flakes brown spots in teeth Deficiency caries Iron Public Health concern Found in 2 forms Heme Non heme iron Functions 1 Part of hemoglobin in red blood cells Transport O2 to tissues and picks up carbon dioxide waste from cells 2 Myoglobin 3 Helps enzymes that make neurotransmitters in brain send messages to rest of body 4 Immune function Heme iron Part of hemoglobin and myoglobin animal sources and easily absorbed 25 Non heme Not as easily absorbed 17 plant foods Daily needs Men and women 50 8 mg day Women 19 50 18 mg day Body only absorbs 1015 of iron consumed Absorption increases if body stores are low Remember heme iron is absorbed more Bioavailability animal heme higher Source s of non heme iron Iron enriched bread and grain products legumes apricots potatoes To enhance absorption of non heme iron KNOW THESE RECOMM Consume food with high Vitamin C eat PB iron with OJ Consume w meat fish poultry heme products Cook foods in iron pans or skillets It is estimated that as much as 80 of the world s population may be iron deficient and 30 suffer from iron deficiency anemia Most common nutritional deficiency worldwide Iron deficiency anemia Microcytic anemia B6 HB MB females poverty pregnant women and growing children are at risk of iron deficiency Too much iron from supplements Constipation nausea vomiting diarrhea Iron overload can damage heart kidneys liver nervous system Hemochromatosis A genetic disorder can cause iron overload Leading cause of accidental poisoning deaths in children under 6 years Copper Aids in iron absorption in small intestine so helps reduce risk of iron deficient anemia Cofactor for antioxidant enzyme CuZn Superoxide Dismutase SOD so a ProAntioxidant FYI Good Sources Organ meats Seafood Chocolate Nuts Seeds Whole Grains Zinc Most abundant intracellular trace element Gene expression DNA synthesis Growth and Development children Cofactor for 300 enzymes e g CuZn SOD Pro Antioxidant for protecting cells from free radical damage Toxic in excess can decrease Cu bioavailability Selenium Se May help to fight cancer another Pro antioxidant Cofactor for antioxidant enzyme Glutathione Peroxidase Iodine FUNCTIONS Used by thyroid to make thyroid hormones regulate metabolic rate and helps heart nerves muscle intestines function normally SOURCES Iodized Salt Salt water fish Deficiency in adults Goiter in children iodine deficiency Cretinism during development shorter and mental retardation problems Problem in developing countries