Males zinc absorption

Almost all the evidence showing that phytate decreases zinc absorption in man and animals is based on pure phytate added to the diet. The effect of natural phytate is variable (18). It has, however, been reported that phytate in bran affected zinc bioavailability in the same way as sodium phytate (19). Dietary fibre in the rural Iranian diet was considered to be the main cause of zinc deficiency in Iran (20). However, the addition of 26 g of fibre from various sources to the American diet did not have any significant effect on the zinc requirements of male adults (21). Similarly, Indian men consuming a diet containing only 10.8 mg of zinc were reported to be in balance in spite of a dietary fibre intake of 50 g per day (22). Moreover, the presence of fibre and phytate in soy flour did not affect the bioavailability of zinc added as zinc carbonate, to the diet of rats (17), although others (23) have reported that the bioavailability of zinc in breakfast cereals depends mainly on their phytate-zinc molar ratio. Our results indicate that there is some, as yet, undetermined difference in the phytate or the fibre of cereals which affects the bioavailability of zinc. It may be some component of dietary fibre (24) or the intrinsic differences in the protein-phytate-mineral complex (10). 

Several zinc absorption studies, using oral doses of ZnCl2 were carried out. 65zq plasma levels were determined serially on the day of the oral administration of the zn tracer. Urinary and fecal 65zn excretions were determined for approximately 15 days. The subjects studied were fully ambulatory males who were In good nutritional state. They were normal according to all clinical and laboratory criteria. Including the serum levels of zinc, calcium, and phosphorus. The effect of three Intake levels of calcium on the zinc balance was studied, namely, of 200, 900,... 

Up to 30% of ingested zinc is absorbed from the small intestine however, a homeostatic mechanism controls the absorption. Nutritional status also influences zinc absorption deficiency of pyridoxine or tryptophan somewhat inhibits absorption. Zinc induces a zinc metallothionein, the form in which it is bound to the liver and other tissues. The pancreas is high in zinc, and in males the prostate gland contains the greatest store of zinc. Zinc is excreted in the feces. 

Studies were carried out In adult males to determine the effect of phosphorus, magnesium, fluoride and zinc on the availability of calcium for absorption ... 

Stable isotopes of iron zinc and copper have been given to subjects in a variety of studies at our Center Standard doses were 4 nig Fe> 4 mg Zn and 2 mg of Cu for adult subjects Isotopes were fed in a single dose in juice at breakfast or in Trutol (a flavored glucose solution) While doses of this size are not truly tracer doses they are in the physiological range of intake Recommended daily intakes are 10 mg Fe 15 mg Zn and 2- 3 mg Cu for adult males (11) Table II shows the average absorption values obtained from subjects who were consuming diets adequate in all minerals and other dietary components ... 

Phytates—These poorly utilized compounds of phosphorus—which are present in the outer layers of grains—bind with such minerals as calcium, iron, and zinc and interfere with their absorption. Hence, mineral deficiencies may occur in people whose diets are composed mainly of whole grain breads. For example, diets based upon these breads were found to be the cause of combined zinc and protein deficiencies which led to stunting of growth and impaired sexual development of males in rural Iran. ... 

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