Marginal vitamin B-6 deciency decreases plasma (n-3) and (n-6) PUFA concentrations in healthy men and women

Abstract

Previous animal studies showed that severe vitamin B-6 deciency altered fatty acid proles of tissue lipids, often with an increase of linoleic acid and a decrease of arachidonic acid. However, little is known about the extent to which vitamin B-6 deciency affects human fatty acid proles. The aim of this study was to determine the effects of marginal vitamin B-6 deciency on fatty acid proles in plasma, erythrocytes, and peripheral blood mononuclear cells (PBMC) of healthy adults fed a 28-d, low-vitamin B-6 diet. Healthy participants (n = 23) received a 2-d, controlled, vitamin B-6-adequate diet followed by a 28-d, vitamin B-6-restricted diet to induce a marginal deciency. Plasma HDL and LDL cholesterol concentrations, FFA concentrations, and erythrocyte and PBMC membrane fatty acid compositions did not signicantly change from baseline after the 28-d restriction. Plasma total arachidonic acid, EPA, and DHA concentrations decreased from(mean6SD) 548696 to 490 6 94 mol/L, 37 6 13 to 32 6 13 mol/L, and 121 6 28 to 109 6 28 mol/L [positive false discovery rate (pFDR) adjusted P < 0.05], respectively. The total (n-6), (n-3) PUFA ratio in plasma exhibited a minor increase from 15.4 6 2.8 to 16.6 6 3.1 (pFDR adjusted P < 0.05). These data indicate that short-term vitamin B-6 restriction decreases plasma (n-3) and (n-6) PUFA concentrations and tends to increase the plasma (n-6), (n-3) PUFA ratio. Such changes in blood lipidsmay be associatedwith the elevated risk of cardiovascular disease in vitamin B-6 insufciency. © 2012 American Society for Nutrition.