Estimated conversion of a-linolenic acid to long chain n-3 polyunsaturated fatty acids is greater than expected in non fish-eating vegetarians and non fish-eating meat-eaters than in fish-eaters
There has also been discussion about just how much ALA from plant sources gets converted to DHA/EPA. The concerns have been that ALA intake is not enough to keep elevated levels of DHA/EPA without additional supplementation.
Two comments here…first, the conversion seems to be greater than originally thought in several studies, including this one. Second, ALA has it’s own benefits in clinical studies on cancer risk and CVD. The bottom line is that I feel we should get a strong balance of plant based and fish based EFAs. Of course, we could then point out that the ultimate origin of fish based EFAs is algae.