Fish oil, EPA, DHA, and Triglyceride forms
Several studies showed benefit of omega 3s in treating macular degeneration, especially the geographic atrophy form.
But not AREDS 2.
Most common omega 3s are a mixture of EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), which are considered “long-chain” omega 3s.
There is debate about why AREDS 2 might not have found benefit. Reasons include not enough used, more EPA than DHA, and failure to use the triglyceride form of omega 3s.
Triglyceride form omega 3s are re-esterified back to their natural 3-chain format, as they are found in nature. This is felt to improve both absorption and potency.