Were We Wrong About Saturated Fat?
By Jennifer Morganti, ND, NEEDS Director of Education
Saturated fat has had a bad reputation since as far back as I can remember. It is believed to cause heart disease, but where did this "fact" come from? An article published by an affiliate journal of the British Medical Journal, called Open Heart, addresses this topic. This progressive article admits to our failings in treating cardiovascular disease and how the standard approach of lowering cholesterol levels is missing the mark. I couldn't agree more, so I was very open to hearing their alternative perspective on saturated fat.
The author, Dr. DiNicolantonio, explains that the negative news about saturated fat started with researcher Ancel Keys several decades ago. It was based on data he gathered from six countries, which ultimately incriminated fat calories as the cause for degenerative heart disease and increased risk of death. Unfortunately, Keys (allegedly) deliberately neglected to acknowledge all of the other data he had that didn't support his theory. There were 16 other countries, which if included, would have significantly weakened his theory that saturated fat was the enemy.
Based on Keys' manipulated data, nutrition authorities declared that saturated fat was the culprit for heart disease, and now we believe that as a fact. To this day, dietary recommendations for preventing heart disease emphasize severely restricting fat intake, but as a result, carbohydrates tend to take their place. Now, after a few decades of practicing the "low-fat" diet, we find our country faced with epidemic rates of obesity. Where did we go wrong?
DiNicolantonio points out that low-fat diets do lower total cholesterol, but studies do not demonstrate that low cholesterol actually reduces the risk of death or infarction. Aiming for low total cholesterol should not be the end goal; we need to reconsider which test parameters are important. It's not just total cholesterol, or even LDL and HDL, because they aren't specific enough. A low-fat diet actually increases sdLDL particles (small-density LDL), which are a major factor in promoting atherosclerosis. However, large LDL particles, which are vessel protective, should be increased. And this is why Keys was wrong; research shows that saturated fat actually increases the beneficial large LDL particles. Another interesting note is that at least one study shows that statins fail to decrease levels of the dangerous small LDL particles, and may actually increase them.
An additional downside to avoiding saturated fat is that we have since increased our intake of PUFA (polyunsaturated fats, from plants) fats, thereby increasing our intake of omega-6 fats, but not omega-3s. Plant fats are not unhealthy on their own, but when there is a great imbalance in the ratios of omega- 3:omega-6, inflammation ensues. The overconsumption of omega-6 has led to an increased risk for many diseases, as well as a greater risk of death, as shown in several studies.
DiNicolantonio makes great recommendations such as: avoid processed foods, eat a diet rich in fruits and vegetables, and increase omega-3 fats. It may take some time and more research to turn around our philosophy about fat and heart disease, but articles like this one are helping to point us in the right direction.
DiNicolantonio JJ. Open Heart 2014;1:e000032. doi:10.1136/openhrt-2013-000032 Tex Heart Inst J. 2010; 37(4): 421–428.