Adding folic acid and vitamins B6 and B12 may enhance the effects even more, according to findings published in Nutrition Research.
“This study updates the literature on the efficacy of omega-3 PUFAs for lowering plasma homocysteine concentration by pooling the results of 21 omega-3 PUFA supplementation trials,” wrote the researchers. “This is the first study to explore the effects of omega-3 PUFAs both with and without folic acid and B-group vitamins.”
Increased concentrations of the amino acid homocysteine have been linked to a range of detrimental effects, including lower bone mineral density in women, and an increased risk of cardiovascular and neurological disease, explained Samantha Dawson, Steven Bowe, and Timothy Crowe from Deakin University.
Tissue and plasma concentrations of homocysteine are known to be determined by vitamin B status, as they are cofactors for enzymes involved in homocysteine metabolism. However, intervention studies with B vitamins to lower homocysteine levels and improve health outcomes have yielded inconsistent results. The data is even more inconsistent for omega-3 interventions.
B vitamins and omega-3s
Data from the VITACOG trial published last year in the American Journal of Clinical Nutrition indicated that high-dose B vitamin supplementation slowed brain wasting (atrophy) in people with mild cognitive impairment (MCI) by 40% but only when omega-3 levels were already high.
On the other hand, in people with low blood levels of omega-3, supplements of folic acid plus vitamins B6 and B12 had no beneficial effect.
In an accompanying editorial, Imrich Blasko from Innsbruck Medical University in Austria wrote that, even with the study’s small number of participants and the need for the findings to be repeated, the study has “important implications”.
By pooling data from 13 trials with omega-3 PUFA supplementation and eight trials with omega-3s combined with B vitamins, the researchers found that 0.2 to 6 grams per day of omega-3s were associated with an 8.5% change in homocysteine from the average baseline.
Data from the 3,267 participants of the trials also indicated that the average homocysteine-lowering effect was greater when omega-3 supplementation was combined with folic acid and vitamins B6 and B12, compared to omega-3s alone.
“A combination may be more beneficial”
Commenting on the potential mechanism of action for omega-3s to lower homocysteine, Dawson, Bowe, and Crowe noted that studies showed that the omega-3 fatty acid DHA may promote pathways involved in homocysteine degradation.
“Given the general health benefits of omega-3 PUFAs and the metabolic link between lipid and homocysteine metabolism, the potential effect on disease might differ when homocysteine is lowered with omega-3 PUFAs as opposed to folic acid,” they wrote. “[R]ather than supplementing with omega-3 PUFAs alone, a combination of omega-3 PUFAs, folic acid and B-group vitamins may be more beneficial for the goal of reducing homocysteine.”
Source: Nutrition Research
Published online ahead of print, doi: 10.1016/j.nutres.2016.03.010
“A combination of omega-3 fatty acids, folic acid and B-group vitamins is superior at lowering homocysteine than omega-3 alone: a meta-analysis”
Authors: S.L. Dawson, S.J. Bowe, T.C. Crowe