Omega-6 Fatty Acids and Cardiovascular Disease: Friend or Foe?
The once-settled roles of all dietary fatty acid classes vis-à-vis coronary heart disease (CHD) seem to be under fire these days. For decades it had been received wisdom that "saturated fats are bad," and that margarines should replace butter to reduce risk for heart attacks. But a recent Time magazine cover that screamed, "EAT BUTTER" illustrates this changing perspective1. Olive oil, the poster child of the "Mediterranean Diet" and a rich source of oleic acid, has long been nearly worshiped as cardioprotective, but recent meta-analyses2 and animal feeding studies3 are challenging this view. Similarly, the marine-derived omega-3 fatty acids, which have historically found a place among the "healthiest" of all dietary fats have fallen on hard times based on the null findings in several recent randomized trials4, and now linoleic acid (LA), the principal vegetable-oil derived omega-6 fatty acid - once taken as a medicine by the tablespoon to lower cholesterol - is now being accused of causing, not preventing heart disease5. The only class that seems to be holding its own is the industrially-produced trans fats which, although clearly promoting CHD, are also slowly disappearing from the American diet6. Understandably, the American public is becoming jaded when it comes to official proclamations of what constitutes a "healthy fat."
- Received August 19, 2014.
- Accepted August 22, 2014.