The British Heart Foundation says some foods, like oily fish, can help control blood cholesterol and lower your risk of heart disease. The Food Standards Agency recommends eating at least two portions of fish a week, with at least one being an oily fish such as salmon, mackerel or sardines. Studies show fish oil can lower triglycerides -- a kind of fat that can contribute to an increased risk of heart attack or stroke if your blood levels are too high.
It's best to get the benefits from food – but supplements providing 2-4 grams of the omega-3 fatty acids EPA and DHA daily can help lower your triglycerides and may even increase levels of good cholesterol (HDL).
In some cases, fish oil supplements can increase LDL cholesterol in people with high triglycerides. It can also cause problems if you are on blood thinners, so always check with your GP or pharmacist before taking supplements.