Micronutrients & recovery
Direct supplementation of EPA and DHA is significantly more effective for increasing their levels in the body than consuming their precursor, alpha-linolenic acid (ALA), due to inefficient conversion rates in humans.
If you are not eating fatty fish regularly, do not rely solely on plant sources like flaxseed or walnuts (ALA) to get your omega-3s. Your body converts ALA to EPA and DHA very poorly. To ensure adequate levels for heart and brain health, consider direct supplementation with EPA and DHA, such as from fish oil or algae oil.
The efficiency of directly supplementing with EPA to increase the level of EPA was found to be 15-fold that of supplementing with high levels of ALA. The conversion rate of ALA to DHA in infants is only 1%, and is even lower in adults... Therefore, the rate of conversion of ALA to EPA and DHA that is required for health is far from sufficient; direct intake of EPA and DHA is more effective.
Why this rating
The paper cites specific tracer studies (carbon isotope labeling) and reviews by Brenna et al. supporting the low conversion efficiency.
Source
Nutritional Indices for Assessing Fatty Acids: A Mini-Review
Jiapeng Chen et al. · International Journal of Molecular Sciences · 2020
This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →