Plasma total homocysteine response to oral doses of folic acid and pyridoxine hydrochloride (vitamin B[sub 6]) in healthy individuals. Oral doses of vitamin B[sub 6] reduce concentrations of serum folate.

Plasma total homocysteine response was compared in four groups of healthy individuals given orally divided doses of vitamin supplementations for a duration of 5 weeks. The vitamin supplements; A, 0.3 mg folic acid; B, 120 mg vitamin B[sub 6]; C, combination of 0.3 mg folic acid and 120 mg vitamin B[sub 6] or D, 0.6 mg folic acid reduced the concentrations of plasma total homocysteine 20, 17, 32 and 24%, respectively. However, the intergroup comparisons did not show a significant difference in the effects of vitamin supplements. Multivariate analysis with correction for differences in pre-supplement values indicated a significant effect of vitamin B[sub 6] supplementation on plasma total homocysteine and serum folate. Our data show that plasma total homocysteine concentrations are reduced with low to medium divided doses of folic acid alone or in combination with vitamin B[sub 6]. [ABSTRACT FROM AUTHOR]