A slew of recent magazine and newspaper articles is introducing laypeople to what holistically-minded healthcare practitioners have recognized for years: the advice to severely limit dietary fat in favor of starchy carbohydrates-which has been institutionalized and entrenched in government nutrition recommendations, with popular belief following in lock-step-may, in fact, be one of the primary drivers of the obesity and chronic disease epidemics it was originally intended to prevent.
The first step was the popularization of the Mediterranean diet, thanks to mainstream medicine's embrace of monounsaturated fats-most commonly found in olive oil, avocado, and nuts and seeds-as well as the omega-3 polyunsaturated fatty acids (PUFAs) found in fatty cold water fish, flax, and chia. But what is really making headlines these days is the massive shift in thinking regarding saturated fats-the ones found in many of the foods we have long been advised to avoid for the sake of heart health and maintaining a healthy body weight: red meat, butter, full-fat dairy, and egg yolks.
The turning of this tide owes itself to a growing body of scientific literature supporting the efficacy of reduced carbohydrate diets-even ones that contain relatively high amounts of not just total fat, but of saturated fat, in particular-for improving a wide array of health conditions, including diabetes, PCOS, heart disease, hypertension, and multiple features of metabolic syndrome.
Researchers who have surveyed the body of evidence supposedly linking saturated fats to a slew of health woes have come to some surprising conclusions. According to a study published in the American Journal of Clinical Nutrition, "There is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of coronary heart disease or cardiovascular disease." And, "Despite the conventional wisdom that reduced dietary saturated fat intake is beneficial for cardiovascular health, the evidence for a positive, independent association is lacking." This reflected an earlier AJCN paper, which found that, regarding the influence of saturated fat on heart disease, "The evidence is not strong, and, overall, dietary intervention by lowering saturated fat intake does not lower the incidence of nonfatal CAD; nor does such dietary intervention lower coronary disease or total mortality."
Other researchers have reported similar findings: "The lack of any clear evidence that saturated fats are promoting any of the conditions that can be attributed to PUFA makes one wonder how saturated fats got such a bad reputation in the health literature. The influence of dietary fats on serum cholesterol has been overstated, and a physiological mechanism for saturated fats causing heart disease is still missing."
Dwight Lundell, MD, a heart surgeon with over a quarter-century in practice, has said, "The science that saturated fat alone causes heart disease is non-existent. The science that saturated fat raises blood cholesterol is also very weak. Since we now know that cholesterol is not the cause of heart disease, the concern about saturated fat is even more absurd today." Moreover, he goes on to affirm that some of the poor health outcomes medical practitioners commonly see today are the result of overconsumption of the PUFAs that were recommended in place of the naturally occurring saturates: "Mainstream medicine made a terrible mistake when it advised people to avoid saturated fat in favor of foods high in omega-6 fats." We have "simply followed the recommended mainstream diet that is low in fat and high in polyunsaturated fats and carbohydrates, not knowing we were causing repeated injury to our blood vessels. This repeated injury creates chronic inflammation leading to heart disease, stroke, diabetes and obesity."
Not only are biochemical mechanisms for the supposed dangers of saturated fats largely lacking, but evidence is accumulating that certain types of saturated fats-specifically, the medium-chain triglycerides found in coconut and palm kernel oils-may be beneficial, particularly regarding cognitive function and neurodegenerative diseases.
Of course, the vindication of saturated fat is not an excuse for patients to load up on the bacon. But the good news is, they might be willing to eat a lot more vegetables now, knowing it's okay to melt a nice pat of butter on top!