well the study said more research is needed to try to figure out why so obviously they are indirectly saying they arent 100% sure... too many variables frankly, hereditary, individuals body make up, enviromental factors responsible for an individuals natural response to adapt and survive....
me personally, i like to think things are relative and when it comes to both heredity and an individuals body make up I think of myself with all the "addictive" drugs I take, I have the will power and ability to stop whenever freely, this includes a plethora of narcotic painkillers and I do mean a plethora, in my lifetime of experiences and resources I tried even a good deal of high powered hg pharm ones by IM/IV by both legit medical reasons and recreationally just out of curiousity, various benzos, booze and nicotine... drugs proven to have both physical and psych dependency...
Now I wont say the times I chose to hang up the fun and come clean from any of them was a walk in the park since a detox period is what it is and there is some pain encountered in the reality of cleansing the body of certain things, but I've never once been "hooked" like some people have and I have both biological grandfathers die early painful deaths from alcoholism, so if the trait or gene etc skipped a generation to me I guess adapted to still be able to drink like a fish but by choice not need...
so when it carries over to this study whats not to say some of the individuals arent more sensitive to the fish oil than others.. or maybe the people they picked where just naturally more prone to prostate cancer or like they mentioned the high dose part.. I can understand too high a dose would lessen the body's natural inflammatory response process which would better fight off the cancer but what is "too high" and is it individually subjective do to ones individual body make up.... if anything I wouldnt take this study at face value to stop taking fish oils but proceed with caution and moderation... I personally just take one enteric coated one-a-day fish oil from costco daily but as of late due to my injury have bumped it to two a day with the hope and luck it may help expedite healing... as for the guys taking a shit load... well may want to just take half a shit load and go from there LOL