If you do gain weight, polyunsaturated fats may prevent some damage

Muffins — and other fatty foods — can definitely put on the pounds, but those made with polyunsaturated oil may be safer for your heart than if they are made with saturated fats like butter, a study published in the Journal of the American Heart Association suggests.
That is because olive oil, sunflower oil and other polyunsaturated fats that include safflower oil, corn oil, soybean oil and canola oil, will not increase bad cholesterol like butter or palm oil, the researchers found.