However, recent research has found that soy probably does not play a direct role in lowering cholesterol. More likely, people benefit from soy because they eat it in place of higher-fat animal proteins.

“My suggestion is you should take soy not as a supplement but as part of your protein mix,” says David J.A. Jenkins, MD, PhD, director of the Risk Modification Centre at St. Michael’s Hospital in Toronto.

Best sources: Roasted soybeans, tofu, tempeh and edamame – baby soybeans that are steamed in their pods.

How much: Aim for 25 grams a day, or about half your daily protein intake. Four ounces of tofu, about 1/3 of a 14-ounce package, for example, contains about 10 grams of protein.

Omega-3 Fatty Acids

What they are: Essential chemical compounds, required for human health, that cannot be made by the body.

How they can help: Omega-3 fatty acids have been shown to calm inflammation, reduce cardiac arrhythmias, or irregular heartbeats, lower triglycerides and help keep plaque from building up in your arteries.

In addition, “Omega-3 fatty acids prevent white cells in the blood from forming a clot so in that aspect, it works like aspirin,” says Paul Marik, MD, a professor of medicine and chief of pulmonary and critical care at Eastern Virginia Medical School in Norfolk. He authored a recent review of 11 studies that determined that dietary supplementation with omega-3 fatty acids significantly reduced the risk of cardiac events in high-risk patients.

Best sources: Supplements; oily fish such as sardines, salmon and tuna; vegetarian sources such as canola oil, walnuts and flaxseeds.