Plasma pyridoxal phosphate concentrations of men fed

The vitamin 8-6 status of 12 white, 3 black, and 7 men of other races was evaluated utilizing plasma pyridoxal phosphate concentrations after the males had been on controlled diets for 8 wk. The diets contained averages of 1.22-1.67 mg/d vitamin 8-6 as calculated from food composition tables. The actual mean vitamin 8-6 content ofthese diets as analyzed with Saccharomyces uvarum was 0.75-0.98 mg/d; the mean daily protein intakes were 80.8-84.5 g. All subjects had plasma pyridoxal phosphate concentrations (67.6-125.8 nmol/L) well within the normal range; the values ofthe different race and dietary groups were similar. Vitamin B-6 requirements were satisfied by the consumption ofdiets analyzed to con- tam means of0.75-0.98 mg/d ofthe vitamin as demonstrated by plasma pyridoxal phosphate levels indicative ofadequate status. Dietary vitamin B-6 intakes should be determined by ac- tual analyses when requirements are being determined. Am J Clin Nutr l988;48:l22-6.