I have been seeing a trend in newer fish oil studies. Many researchers are combining fish oil, with its omega-3 EPA and DHA, with gamma-linolenic acid (GLA), which is an omega-6 fat. Years ago, Jack Challem wrote about this in his book " The Inflammation Syndrome ". Now research continues to show that there is a synergy in these fatty acids in reducing inflammation.
For example, this study on ADHD says:
"Placebo-controlled studies with ADHD or hyperactive children show no effects on behaviors or cognition when only n- 6 (omega-6) PUFA, only docosahexaenoic acid (DHA), or n-6 and n-3 (omega-3) short-chain PUFA are supplemented. Yet three out of four studies suggest that a combination of long-chain n-3 and n-6 fatty acids (DHA, eicosapentaenoic acid [EPA], and gamma-linolenic acid [GLA]) supplemented daily for 3 to 4 months could lead to a reduction in ADHD symptomatology."
Omega-3 fats by themselves weren't effective. Only when combined with GLA were there benefits.
This study shows that the combination of the three fatty acids improves eye health. This study showed the same combination was better at preventing retina damage.
You can get GLA from evening primrose oil or borage oil. Some older studies showed that just GLA was not that effective at reducing inflammation-related conditions. However, GLA may become effective when teamed with EPA and DHA as these newer studies show.