Don't buy into reports that "butter is back." The saturated fat in butter appears to increase the risk of coronary artery disease, and so do the fats found in other dairy foods, meat, lard, and palm oil, suggests a study published Nov. 23, 2016, in The BMJ. Harvard researchers analyzed more than two decades' worth of dietary and health information from more than 115,000 people. Researchers noted that higher intakes of the most common saturated fats—lauric acid, myristic acid, palmitic acid, and stearic acid—were associated with a boost in the risk of coronary artery disease of up to 18%. But replacing just 1% of those fats with the same amount of calories from polyunsaturated fats, whole grains, or plant proteins was associated with a 6% to 8% lower risk. The study doesn't prove that individual saturated fats increase the risk of developing coronary artery disease. For example, stress may have played a part in the risk, but it wasn't measured.
However, the findings echo what current USDA Dietary Guidelines recommend: limit saturated fat intake to less than 10% of total calories, and eat a diet rich in fruits, vegetables, whole grains, nuts, legumes, fish, low-fat dairy, and vegetable oils rich in polyunsaturated fats (sunflower or corn oil) and monounsaturated fats (olive or canola oils).