It isn’t unusual for studies to conflict. It also is not unusual for many people to believe something, and later for science to disprive it, or not be able to confirm the popular belief. We saw this with vitamin C when claims were made it fights the common cold, but the study that supposedly proved this could never be repeated, meaning they never got the same result again of showing a significant improvement among vitamin C megadosers. Another is soy helping with menopause symptoms. Studies show it doesn’t help, but people still believe it does. There was a large study regarding fiber and colon cancer, and contradicting older studies it showed no affect to consume more fiber to keep colon cancer away. Oatmeal claims to lower cholesterol, but with further inspection pretty much any of the whole grain cereals will lead to lower cholesterol. I persinally don’t believe it has anything to do with the grain, I think it has to do with a no cholesterol breakfast vs a cholesterol breakfast, but I am not a doctor or medical researcher.
As far as vitamins and minerals, I am a big believer in testing. Test your blood levels, see if you are dificient. The deficiencies I hear the most are vitamin D, vitamin B12, and for women iron. If omega fatty acids are supposed to help cholesterol ratios and lipids, get a test. Test while not taking the supplement, and then test after and see if there is improvement. It might help you as an individual. Supposedly eating trans fats are worse than eating butter for cholesterol blood levels, but for me taking in cholesterol leads to higher cholesterol numbers for me period. Butter raises my cholesterol.