The first conclusive evidence borne of randomized clinical trials suggests that replacing saturated fats with polyunsaturated fats does indeed reduce heart risks. Harvard School of Public Health (HSPH) researchers looked at eight studies with a total of 13.614 participants, finding that those who replaced saturated fats with the polyunsaturated kind had a 19% lower risk of heart disease than those who didn’t make the change.

The longer subjects stayed on a diet rich in polyunsaturated fats, the greater the benefits. For this research, the authors only used studies where participants increased their polyunsaturated fat foods intake as a replacement for saturated fats, and where any heart events could be documented. For nearly 60 years we’ve been told to reduce consumption of saturated fats to keep heart disease at bay, though there’s been mixed scientific evidence that doing this really cuts the risk.

Saturated fats are the ones found in butter, cheese, bacon and red meat, and are known to raise the levels of bad cholesterol that then block the arteries, especially the coronary arteries. The recommendation is that adults get no more than 11% of daily calories from these type of fats, though the average intake in the U.S. is less, probably 6-7% of total calories. This isn’t any better. the fats from those fat-free cookies, cakes or other foods are hardly nutrition packed choices.

Over the years, the food industry has reduced the amount of saturated facts in many items, often replacing them with just as bad trans fats. The typical American diet often replaces these types of fats with increased consumption of refined carbs and grains. You can get these fats from natural sources like soybean oil, corn oil. Safflower oil, fatty fishes like salmon, mackerel, herring and trout. Other natural sources include walnuts and sunflower seeds.

Heart disease is a known killer, a leading cause of death among adults all over the world. If you’re concerned about your own heart risks, this study affirms that a change in diet be a smart move – replace those saturated fats, but with healthy options like polyunsaturated fats. You best bet according to experts is that you need to eat the right amount of calories in a healthy, balanced way.