Food and nutrition.pdf

74 Nutrientssupplementation of either. It can neutralize certain carcinogens so possiblyprovide protection from some cancers.The best natural sources of selenium are seafoods, eggs anddepending on the selenium content of the soils in which they are grown,grains and seeds.SodiumSodium is the principal cation of extracellular fluid. As the rate ofsodium loss can vary under different conditions there is no official RDA,but the minimum daily requirement for healthy adults is 500 milligrams.Sodium is crucial for regulating the membrane potential of cells andis involved in active transport across cell membranes, it is pumped out inexchange for potassium. It helps the nerves and muscles function properly.Sodium is found in abundance in most processed foods thus there isvery little chance of a deficiency occurring with the average Western Diet.The best natural sources are salt, shellfish, anchovy, lox, spirulina,wakame, cheese and red or green peppers.The body may be depleted of sodium under extreme conditions ofsweating or chronic diarrhea.Excessive intake of sodium can result in edema and hypertension.SulfurSulfur is used to treat many kinds of skin disorders. Sulfur cream,lotion, ointment, and bar soap are used to treat acne. Sulfur ointment isused to treat seborrheic dermatitis and scabies. Sulfur may also be usedfor other conditions as determined by your doctor.ZincThe RDA is 15 milligrams per day for men and 12 milligrams perday for women. Recent research suggests that men have a higher needfor zinc than do women. Thus, it is appropriate that the RDA is sex-specificfor zinc.Zinc is an essential trace element that must be supplied in the diet ofhuman beings so that growth and health can be maintained. It is necessaryfor protein synthesis and the metabolism of vitamin A, it helps the healingprocess of internal and external wounds, decreases cholesterol depositsand promotes mental awareness. A deficiency can cause loss of appetite,growth retardation and immunological abnormalities.The best natural sources are oysters, nuts, wheatgerm, whole grainproducts, brewers yeast meat, eggs, legumes and seeds.Zinc is more easily absorbed in small amounts than large amounts.Human studies have shown that milk apparently inhibits zinc absorption.