RD&T contributor, Dr. Joel Furhman, discusses Omega-3 fatty acid adequacy and the need for DHA by vegans and near-vegans in this article.  In particular, he addresses the importance of eating nuts and seeds to extend lifespan, among other benefits.

Omega-3 Fatty Acid Adequacy

What do nuts and seeds have to do with it?

One thing we know for sure – eating nuts and seeds extends lifespan and eating none or only very small amounts (under a half ounce a day) is a risk factor for all-cause mortality. The link between eating nuts and enhanced lifespan is one of the strongest supported findings in the field of nutritional science in the last two decades.¹⁸

In other words, you can deny that eating more meat is bad or you can try to deny that eating more nuts is good, but the evidence from scores of studies that have looked at this with large populations over many decades, all corroborate each other that eating nuts and seeds has a very powerful effect at reducing cardiac death and especially sudden cardiac death (by arrhythmia). The Physicians’ Health Study even used autopsy data to confirm sudden cardiac death to control for other causes of unwitnessed death and documented reduction of fatal cardiac arrhythmias in those with heart disease with greater nut/seed intake.¹⁹