Omega-3 is thought to increase reuptake of serotonin (the same exact thing that SSRIs, or antidepressants, do). I've also read that it helps in the production of serotonin.
It depends on what you mean by "fad." "Coral Calcium" was a fad. "Natural Cures" was a fad. Omega-3 is backed by legitament research. In fact, we NEED omega-3 fatty acids to build and repair the myelin sheath on nerve cells.
No doubt, but it does seem to be cropping up everywhere. Type in Omega 3 and some body part and you get loads of claims supporting its use. Omega 3 and eyes
As for the eye, I found this study on the first page of your search link. http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=hstat1a.section.91880 Basically, they conclude we do not really know what supplementing omega-3 can do for eye health. I would agree since most every study I see is done with ADHD, depression, and bipolar disorder. However, I have talked to a few people that claim their vision has gotten better for a period of 24 hours after supplementing with very high doses of omega-3 fish oils. I've never tried it but it could just be a temporary effect resulting from "symptom masking" (sort of like when someone puts octane booster into their vehicle to stop the engine from pinging... when the octane booster runs out, the problem shows up again).
Heh.. I would think that omega-3 might cause acne. Does the Internet tell me otherwise? I haven't looked it up.
Frankly, I don't know too much about Omega-3, but could it be instrumental in helping leukodystrophy patients (who suffer from a lack of myelin)?
From what I undrstand, fish-oil and other omega-3s would only relieve some of the symptoms, but it will not cure it because there is a fundamental problem not associated with the fat's role in the body (whatever all those are).