Effect of Dietary Protein, Phosphorus, and Sulfur Amino Acids on Selenium Metabolism of Adult Males

Abstract

Two human metabolic studies were conducted. In the first 51 -day study, selenium utilization was examined in 8 adult males fed a low protein – low phosphorus diet (LPrLP); a low protein – high phosphorus diet (LPrHP); a high protein – low phosphorus diet (LPrLP); and a high protein – high phosphorus diet (HPrHP). In the second 51-day study, selenium utilization was examined in 8 adult males fed an LPrLP diet; an HPrLP diet; a low protein – low phosphorus diet to which methionine and cystine were added (LPrSLP); and a low protein – high phosphorus diet to which methionine and cystine were added (LPrSHP). The methionine and cystine content of the HPrLP, LPrSLP, and LPrSHP diets were all equal. Subjects lost significantly less selenium in their feces, but significantly more selenium in their urine, when they were fed HPrLP and HPrHP diets rather than LPrLP and LPrHP diets. Subjects lost even more selenium in urine when they were fed LPrSLP and LPrSHP diets rather than the HPrLP diet.