Fats–some good, some bad?

Confused about fat intake?  Unless you have been living under a rock, you should be. For almost half a century, the prevailing hypothesis has been that lowering fat, and in particular, saturated fat, is the best way to lower LDL cholesterol, and cardiovascular disease risk yet there are now several lines of contradictory evidence provided by populations that seem to do well in other environments.  Consider the “Mediterranean Diet”, which is higher than 30% fat.  Or the diets of several traditional peoples, such as Innuit, who eat a very high animal fat diet, or the Masai, who eat high amounts of animal fats as well, yet have low risks of heart disease.  So what is the latest on several important questions? Low fat vs high fat.  Saturates vs mono and polyunsaturates.  Some saturated fats vs others. Omega-3s vs Omega-6s. trans fats. Refined oils. Dietary Cholesterol.  Do dietary fats also affect other diseases besides heart disease? Help!

The “lipid hypothesis” has been around for a long time, championed primarily by Ancel Keys, although evidence continues to be contradictory, and several researchers have expressed concerns about the inertia of prevailing opinions, even stating that the entire hypothesis is out of date.


LDL cholesterol is widely regarded as a primary driver of atherosclerotic heart disease, although this premise is being called into question on imaging studies.