Evidence for a protective (synergistic?) effect of B-vitamins and omega-3 fatty acids on cardiovascular diseases

Abstract

The results of dietary intervention trials favor the hypothesis that higher intakes of B-vitamins (folate, vitamin B 6 and B 12 ), and subsequently lower total homocysteine (tHcy) concentrations, are causally associated with a decreased risk of vascular disease in patients with cardiovascular diseases (CVD). The same is true for a higher intake of omega-3 fish fatty acids. Yet, the lack of hard end points and/or appropriate study designs precludes a definitive conclusion about causality. In the future, intervention trials with hard end points and randomized double-blind placebo-controlled designs should be able to elucidate the causality problem. There are several pathways by which B-vitamins and omega-3 fatty acids may exert their protective effect on CVD, a common pathway is a beneficial effect on the endothelial function and hemostasis. With respect to synergy between B-vitamins and omega-3 fatty acids, there is no evidence that fish oils have a tHcy-lowering effect beyond the effect of the B-vitamins. Nevertheless, animal studies clearly illustrate that vitamin B 6 -as well as folate-metabolism are linked with those of long-chain omega-3 fatty acids. Furthermore, a human study indicated synergistic effects of folic acid (synthetic form of folate) and vitamin B 6 together with omega-3 fatty acids on the atherogenic index and the fibrinogen concentration. Although these results are promising, they were produced in very small selective study populations. Thus, confirmation in large well-designed intervention trials is warranted.

The relationship between folate and docosahexaenoic acid in men

“…It is intriguing to consider whether some of the health benefits associated with national policies to enrich grain with folate may be mediated, in part, by improvements in DHA status. Alternatively, DHA and folate might act synergistically to benefit a number of these conditions (de Bree et al, 2004). It would be interesting to investigate the possibility that DHA levels are low in babies born with neural tube defects, a developmental malformation associated with folic acid deficiency.…”

Supplementation with B vitamins or n−3 fatty acids and depressive symptoms in cardiovascular disease survivors: ancillary findings from the SUpplementation with FOLate, vitamins B-6 and B-12 and/or OMega-3 fatty acids (SU.FOL.OM3) randomized trial

“…The study's factorial design necessitated the assessment of an interaction between supplements regarding depressive symptoms even though there is no compelling evidence of synergism between B vitamins and n23 PUFAs (29). With a statistical power of 0.92, which was calculated by using Demidenko's method (30), the estimated interaction was not significant (P .…”

Omega‐3 fatty acid supplementation and total homocysteine levels in end‐stage renal disease patients

“…Published findings regarding the relationship between FO supplementation and tHcy have been equivocal and appear to vary based on sample population, FO dosage and study duration. 5,[10][11][12][13][14] Database searches revealed only one other published study specifically looking at the effect of n-3 fatty acid supplementation on tHcy levels in an ESRD population. 17 Holdt et al studied the effect of 3 months of FO supplementation on tHcy levels in continuous ambulatory peritoneal dialysis patients.…”

“…10 Since Olszewski and McCully's original finding, only a small number of study authors have published the effects of FO supplementation on tHcy, with equivocal findings reported. 5,[10][11][12][13][14] Therefore, the purpose of this study was to examine the effect of an over-the-counter (OTC) n-3 supplementation on tHcy levels in ESRD patients undergoing chronic haemodialysis.…”