Because it's a randomized controlled trial (RCT) rather than an observational study, it's showing causation rather than mere correlation. I imagine the correlations between ω-3 fatty acids (more is better) and homocysteine (less is better) inspired the RCT, but I think the authors do well not to include homocysteine in their conclusions. I love that they avoided fish oil supplementation and simply measured ω-3 fatty acids as it really adds to clarity regarding the value of B vitamin supplementation.
Alas, there's no ε4 breakout.
For my part, I have been betting on the hypothesis that keeping homocysteine below the high end of the reference range with B vitamins, TMG, and NAC; consuming sardines, salmon, grass fed beef, omega-3 eggs, and cod liver oil; and avoiding high omega-6 processed seed oils will be good for me. This paper doesn't prove that my strategy is right, but it certainly bolsters my resolve to continue.
Design: This retrospective analysis included 168 elderly people (≥70 y) with mild cognitive impairment, randomly assigned either to placebo (n = 83) or to daily high-dose B vitamin supplementation (folic acid, 0.8 mg; vitamin B-6, 20 mg; vitamin B-12, 0.5 mg) (n = 85). The subjects underwent cranial magnetic resonance imaging scans at baseline and 2 y later. The effect of the intervention was analyzed according to tertiles of baseline ω-3 fatty acid concentrations.
Results: There was a significant interaction (P = 0.024) between B vitamin treatment and plasma combined ω-3 fatty acids (eicosapentaenoic acid and docosahexaenoic acid) on brain atrophy rates. In subjects with high baseline ω-3 fatty acids (>590 μmol/L), B vitamin treatment slowed the mean atrophy rate by 40.0% compared with placebo (P = 0.023). B vitamin treatment had no significant effect on the rate of atrophy among subjects with low baseline ω-3 fatty acids (<390 μmol/L). High baseline ω-3 fatty acids were associated with a slower rate of brain atrophy in the B vitamin group but not in the placebo group.
Conclusions: The beneficial effect of B vitamin treatment on brain atrophy was observed only in subjects with high plasma ω-3 fatty acids. It is also suggested that the beneficial effect of ω-3 fatty acids on brain atrophy may be confined to subjects with good B vitamin status.
YES, this concept was brought up at our recent conference. B vitamins only work if your omega-3 fatty acid levels are adequate. Very interesting to see that it works both ways.
very crude trial yes it is homocysteine but the amount of B vitamins and the type depend on methylation, saw something like that years ago.
b-12 and folate also possibly B-5 are main ones.
Juliegee wrote:YES, this concept was brought up at our recent conference. B vitamins only work if your omega-3 fatty acid levels are adequate. Very interesting to see that it works both ways.
Both ways? Is there research saying that fish oil supplementation only works if homocysteine is low? I don't suppose you have a study at your fingertips?
You're understanding correctly, Merouleau. The presenter was either Dr. David Smith of Oxford or Dr. Helga Refsum, University of Oslo...I'll look for specific papers. They asserted that B vitamins were only effective in those with good Omega-3 profiles. This could have important implications for vegans with persistently high homocysteine.
The concept that "B vitamins were only effective in those with good Omega-3 profiles" is the same as the conclusion of this paper. When you said "both ways" I thought you meant that causality had been demonstrated in both directions. Maybe I understood your "both ways" remark differently than you intended it ... here's what I think of as "two ways" that might apply here:
1. B vitamin supplementation improves health as long as one has plenty of circulating ω-3 fatty acids.
2. ω-3 fatty acid supplementation (e.g. fish oil) improves health as long as one's homocysteine status is good.
I am aware of evidence for (1) but not yet for (2).
Sorry to be confusing. It is understood that healthy vitamin B levels confer low homocysteine.
When I referred to the synergistic effect working both ways; I meant vitamin Bs are only effective in the presence of healthy ω-3 fatty acid levels AND ω-3 fatty acids are only effective in the presence of healthy vitamin B levels.
Conclusions: The beneficial effect of B vitamin treatment on brain atrophy was observed only in subjects with high plasma ω-3 fatty acids. It is also suggested that the beneficial effect of ω-3 fatty acids on brain atrophy may be confined to subjects with good B vitamin status.
Julie, what was said at the conference about this please? It's all new to me.
(small diversion : What does everyone feel is achievable and necessary for a homocysteine level? For instance mine is 8 to 9. I remember someone at the NYC conference mentioned 6 as target (eeek))
Conclusions: The beneficial effect of B vitamin treatment on brain atrophy was observed only in subjects with high plasma ω-3 fatty acids. It is also suggested that the beneficial effect of ω-3 fatty acids on brain atrophy may be confined to subjects with good B vitamin status.
I read the second sentence as a plausible add-on speculation - "also suggested", "may be" - rather than a true conclusion, so I didn't make the connection to your "both ways" remark. I get it now.
