title: Comparative vitamin B-6 bioavailability from tuna, whole wheat bread and peanut butter in humans.
abstract: Relative bioavailability of vitamin B-6 from tuna, whole wheat bread and peanut butter was investigated in eight men. The study was divided into a 10-day adjustment and three, 14-day experimental periods in a 3 X 3 Latin square design. Vitamin B-6 intake was set at 1.6 mg/day, with 50% of the intake coming from one of the three experimental foods and 50% from a basal diet. Daily complete urine and fecal collections were made. Urine was analyzed for 4-pyridoxic acid (4PA) and vitamin B-6, fecal samples for vitamin B-6 and plasma (sampled every 5 days) for pyridoxal 5'-phosphate (PLP). Mean values +/- SD for the adjustment, tuna, whole wheat bread and peanut butter periods were: 5.65 +/- 1.76, 4.89 +/- 1.10, 3.62 +/- 0.66 and 2.80 +/- 0.50 mumol/day for 4-pyridoxic acid; 0.98 +/- 0.34, 1.05 +/- 0.20, 0.76 +/- 0.09 and 0.68 +/- 0.19 mumol/day for urinary vitamin B-6; 2.72 +/- 0.94, 3.08 +/- 0.73, 3.80 +/- 0.78 and 4.42 +/- 1.03 mumol/day for fecal vitamin B-6 and 65.0 +/- 23.30, 64.8 +/- 29.80, 49.3 +/- 14.40 and 48.4 +/- 20.20 nM for plasma pyridoxal 5'-phosphate, respectively. 4PA and urinary vitamin B-6 excretion were significantly (P less than or equal to 0.01) higher in the tuna period than in either the whole wheat bread or peanut butter periods.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000328:Adult; D000818:Animals; D010367:Arachis; D001682:Biological Availability; D001939:Bread; D005243:Feces / Q000032:analysis; D005399:Fishes; D005519:Food Preservation; D006801:Humans; D008297:Male; D011732:Pyridoxal Phosphate / Q000097:blood; D011735:Pyridoxic Acid / Q000652:urine; D011736:Pyridoxine / Q000032:analysis / Q000378:metabolism*; D013997:Time Factors; D014413:Tuna
chemical_list: D011735:Pyridoxic Acid; D011732:Pyridoxal Phosphate; D011736:Pyridoxine