I was wrong about the original researcher of the "Seven Countries" study, he was Ancel Keys and he was not an MD. He badly cherry picked data and hid is own follow on study results which proved his theory on cholesterol wrong. His bad work led us down a path of bogus anti fat theories that have been disastrous from public health.
The cholesterol war on saturated fats has been proven to be bogus, but Omega 3 oils- both plant and animal (fish and grass fed ruminants) have proven important as anti-inflammatory, even if the cholesterol link is highly suspect. One of the common tricks used by big Pharma is to run a bunch of studies, and disappear those which reveal bad results and/or dangerous side effects. 1% better than placebo is enough to get approval. If you run enough studies that can happen, especially if you hire unscrupulous researchers. You also see this type of pharma crap happening with the MS drugs. $30-50K per year and virtually no change in the 10 year outcome.
Like most with MS, I have a lot of pain, and find Omega 3's plus reduced plant Lectins reduce it by 75% if I'm careful with my diet. I eat wild caught fish instead of taking oil or pills. Lectin theory is new and suspect but I was rather flabbergasted that it worked for me and accurately predicted those foods which I had previously found increased my pain greatly (grains, legumes). I have a high level of skepticism, but I do believe in results, even if not the why.
Organic veges, wild caught fish and grass fed lamb, beef and goat are very expensive where I live but I am fond of being able to living independently, and lower levels of pain improve my quality of life.