B Vitamins: No Impact on Cardiovascular Outcomes Review Finds

the MPR take:

A review published in PLOS One has found that B vitamin supplementation does not significantly reduce major cardiovascular outcomes despite prior observational studies suggesting supplementation may reduce cardiovascular risk. Twenty-four randomized clinical trials of 57,952 were assessed for major adverse cardiovascular events (MACE) and the effect of B vitamin supplementation on cardiovascular outcomes. B vitamin supplementation reduced the risk of MACE overall by 2%, but this was not statistically significant (RR, 0.98; 95% CI: 0.93–1.03; P=0.37); no significant difference in mortality was observed between those receiving B vitamins compared with placebo (RR, 1.01; 95% CI: 0.97–1.05; P=0.77). B vitamin supplementation did result in a 4% reduction in cardiac death, but this was not a significant change. Thus, the authors do not see the justified use of B vitamin supplementation as a structured intervention in everyday clinical practice.

Observational studies suggest that B vitamin supplementation reduces cardiovascular risk in adults, but this association remains controversial. This study aimed to summarize the evidence from randomized controlled trials (RCTs) investigating B vitamin supplementation for the primary or secondary prevention of major adverse cardiovascular outcomes and to perform a cumulative meta-analysis to determine the evidence base.