Fish contain omega polyunsaturated fatty acids (PUFA.) The following are the three main PUFA’s in the human body:
alpha linolenic acid (as in flax seed.)
eicosapentaenoic acid (EPA.)
docosahexaenoic acid (DHA.)
Humans can’t make linolenic acid. We can convert the alpha linolenic acid in flax seeds to EPA and DHA. EPA and DHA store in the body fat. Fat tissue biopsy seems to be the most accurate indicator of fish consumption in humans. The author says it is a very simple procedure and could be used for future studies.
CONCLUSION: Fish oil contains EPA and DHA. Flax seeds contain alpha linolenic acid which the human body can convert to EPA and DHA. These are the main PUFA’s of the human body.