We have been thinking for decades that Omega 3, largely taken as fish oil supplements, would fight cholesterol and help us maintain a very healthy cardiovascular system.
But Omega 3 supplements have been backed by mixed evidence lately with regards to its benefits to heart health; don't throw them away, though, because they are still considered highly beneficial for your overall health (including your mental health) and, maybe, the quality of your blood flow.
I therefore do not discount it, in fact I am still using this supplement daily for overall health, preferably from 'Krill'; to avoid ingesting mercury, use Omega 3 with a specific guarantee of distillation (stripped of mercury) or, as mentioned, Krill supplements.
In the past Omega 6 supplements were mixed with Omega 3 ones and sold on their own 'benefits'.
However, with a few set of exceptions, Omega 6 supplements are now being regarded as the type of oil to avoid, at least in large quantities; they seem to promote inflammation of the arteries, though of course it's early days (but why take the risk?).
Ironically, years ago, when I was ingesting Omega 6 supplements, I felt that my rheumatoid arthritis would worsen rapidly; at the time there was no real information on this but I tend to 'listen to my own body' above everything else (something I would advise anyone to learn to do).
I would therefore recommend avoiding supplements with Omega 6 and stick to Omega 3 (at least, this is my personal advice based on the latest studies).
However, the one oil you can continue to consume without any concern is Extra Virgin Olive Oil, cold pressed, ideally from a reputable source and organic (but it's expensive so at least buy any extra virgin kind).
Any other oil or margarine (or butter) must be avoided.
Research has also promoted to the top natural ways to help your cardiovascular health, some of them seriously overlooked in the last few years; the following are 3 of them: 1 - Eating large amounts of fresh organic garlic (if you can) for its cholesterol-lowering benefits, its pressure-lowering benefits and its overall 'cleansing' properties.
Buy organic garlic, cut some finely, let it sit for a few minutes to allow the powerful 'allicin' to come through, and then use it to dress your dishes, such as your home-made hummus (my favorite way to eat fresh garlic).
You can also add it (mixed with extra virgin olive oil, raw, not cooked nor heating up) to your home-made pizza or your regular pizza (but read on about white carbohydrates).
Another way is to add it to your wholegrain pasta dishes, or your mash potatoes, or in any dish where raw garlic is suitable, such as bruschetta.
2 - Decreasing the amount of WHITE carbohydrates (whole grains are fine): so avoid white base pizza, white pasta, white rice, white bread, cookies and anything made with white (enriched) flower; consume only whole-grain carbohydrates.
Also, avoid sugar, artificial sweeteners and stick to stevia and to naturally-made granulated honey (not refined honey, which is as bad as sugar).
Diabetes is very detrimental to your overall cardiovascular health.
Moreover, white carbs and sugar (as well as artificial sweeteners) carry a large number of detrimental effects on your body.
3 - Consuming freshly squeezed lemon juice with spring (not tap) water several times a day - tap water is fine if it's directly from a spring, like, for example, in some mountain springs areas.
Research has shown that fresh lemon juice (without sugar!) in your glass of water (many times a day) helps 'cleanse' the arteries.