Let's start with some terms. Let's call an artificial or synthesized substance that we consume in addition to food a drug, and a more or less "natural" substance in artificially concentrated amounts a supplement.
It should be obvious by now that I generally don't believe in drugs or supplements. If you are deficient in a substance that you are not getting in your diet or that your body would normally manufacture but doesn't, that is replacement. Examples: a 35 year old woman who is hypothyroid due to autoimmune disease from eating wheat needs to take synthroid; a 42 year old woman has premature menopause from a lifetime of hyperinsulinism and uses hormone replacement therapy; a Naval officer does a three month underwater tour on a nuclear submarine and takes vitamin D to compensate for his deficit of normal Vit D production caused by lack of exposure to UVB from sunlight.
If one eats properly in a manner to which we are adapted, the law of unintended consequences would dictate that introducing extra amounts of any specific substance, whether a "natural" micronutrient, a "vitamin" or a big pharma drug developed in a laboratory, is more likely to do harm than good, the same way randomly adding a part to a piece of carefully designed machinery is more likely to screw it up than improve it.
My reading of the available evidence is that supplementation only is of benefit if you are actually deficient in something. Trials of "excess" antioxidant vitamins have provided zero benefit, for example.
If you are supplementing with fish oil, it is to counteract the excess Omega 6 fatty acids in your diet. Maybe we should call that compensatory supplementation - you are compensating for something screwed up in your diet.
It is far and away preferable just to not eat the excess Omega 6 fatty acids in the standard american diet in the first place.
Don't cook with seed oils. Corn, canola (rapeseed), peanut, saffllower, cotton, margarine, even olive oil.... are all seed oils.
Don't eat processed or fried foods that contain them.
If you are eating lots of seed oils, you would have to take quite a lot of fish oil to counteract the effects of the excess O 6s. It may help, but is much closer to the EM2 to just cut out the O-6s in the seed oils.
My advice to take the fish oil was a bit of a throwaway. It is more theoretical than proven, and I don't do it myself as I mostly eat wild game or grass-fed bison and only infrequently eat chicken or pork.
Visit Peter's blog here and read his biochemistry heavy posts for his rationale on this. He points out that the Pork and Chicken may be more of a worry than the beef regarding the fatty acid ratios, but remember that he is in the UK and beef here in the 'states is likely worse as it's more corn fed.
Peter points out that extra O 3 fatty acids may not be healthy if you have high carb consumption, but are probably good on LC and high fat diet.
It is all rather complex. Do you see my point now about randomly "improving" a presicion machine and assuming it will run better?
PaNu assumes the machine will run best on the proper fuel, not that adding a magic ingredient to the gas tank, (like STP in the 1960's) will make it run better!
Possible sources of fish oil include cod liver oil and sardines tinned in olive oil or water. I do eat a few sardines because I like them.
I take no fish oil.
I do take Vitamin D (which is not a vitamin) and think that is way more important than fish oil. I'll post more on that later, but I will be raising my recommended dose on that soon.