Certainly continuous DHA supplementation seems like a clear negative, for many reasons. I personally have never supplemented with DHA (and EPA only in the past couple of years). However.
Fish contains on average more DHA than EPA. Has regular fish consumption been shown to be brain negative? We do know, that supplementing with DHA in addition or concomitantly with fish does not rescue the negative effects of DHA, which would imply that there is nothing special in the fish food matrix that modifies DHA bio kinetics. Or?
Furthermore, as DHA is distributed in more tissues than just the brain, what would be the impact of intermittent DHA bolus (say, once a week)? We know thereās a clear difference in intermittent vs continuous (after all, we do it with rapa), basically a pulsed intake.
An intervention that has a seemingly negative impact acutely, need not have such longer term, or intermittently or dosage dependent - thousands of well known examples - exercise, impact of certain FA on endothelial function, coffee and BP and BG impact and on and on and on. Hormesis too. We all know this.
So a single image tells me something, but not everything. The scientific method means that we need to prove outcomes, not just rely on extrapolation, however tempting that may be.
We already have some outcome studies of DHA supplementation. On the whole, not very encouraging. But. We do not have - that I am aware of - outcome studies exploring other modalities of supplementation, such as once weekly pulsed. And again, what about fish consumption? Is the rest of the stuff in fish so beneficial that it offsets the negative of DHA? I think that needs to be shown, and there is reason to doubt it, as fatty fish has more DHA, yet is supposedly healthier - it needs to be shown. We can speculate mechanistically all we want, but the proof is in the pudding.
Metabolism and functions of docosahexaenoic acidācontaining membrane glycerophospholipids
