Food and nutrition.pdf

Nutrients 71reasons have habitually had a low intake of iodine, and -those who aresensitive to iodine.The maximum tolerable level of iodine appears to range from 200mcg per day to 1000 mcg per day. These levels of intake are possible fromdiets that include milk, iodized salt, seaweed and products containingthe red food coloring erythrosine which has high levels of iodine.Generally, iodine intakes by the majority of the population in the USAis considered safe and adequate.IronIron is a constituent of hemoglobin. Body-iron content is regulatedby the amount absorbed. The absorption is influenced by body stores andby the amount and type of iron in ingested foods. The RDA for adults is15 milligrams.It is a vital component of many enzymes, it can promote resistance todisease and prevent fatigue. A trend toward reduced risk of melanomawas observed by Stryker et al when iron intake was increased (notincluding supplements). [Styker, W.S., Stampfer, M.J., Stein, E.A, Kaplan,L., Louis, T.A, Sobre, A, and Willet, W.e.: Diet, plasma levels of betacaroteneand alphatocopherol, and risk of malignant melanoma. AmericanJournal of Epidemiology, Vol. 131,:612 1990]A deficiency can cause anemia, resulting in impaired concentration,reduced physical performance and work capacity, and decrease immunefunction. Ascorbic acid is necessary for the proper assimilation of iron.The best natural sources of iron are sea vegetables, clams, cockles,mussels, oysters, yeast, molasses, beans, nuts, seeds and cereals.Tea, coffee, bran and phytates decrease iron absorption.There are no reported cases of toxicity from foods but iron poisoningmay occur from ingesting large amounts of medicinal iron supplements.MagnesiumMagnesium is known as the antistress mineral. The RDA for adultsis 350 milligrams.Many biochemical and physiological processes require magnesium.It is necessary for vitamin C and calcium metabolism. It keeps teethhealthy, brings relief from indigestion and can aid in fighting depression.More than 300 enzymes are known to be activated by magnesium. Itcontrols cellular metabolism and maintains electrical potentials of nerveand muscle membranes for the transmission of impulses across junctions ..The best natural sources are whole seeds, nuts, legumes, unmilledgrains, green vegetables and bananas. , ' ,Phytate or, fi,bre m~y reduce magnesium absorption. Alcohol acts as