For years, we've all heard different takes on fat - limit all fats, avoid specific fats, don't eat fats from certain sources. However, hundreds of clinical trials in the last few decades have failed to confirm that all fats are correlated with disease or weight gain. In fact, many studies have now shown the vital importance of consuming healthy fats for everything from heart and brain function to hormonal health. So how did fat get its bad reputation and what does new research show about this macronutrient? Let's chat.
Why does fat have a bad rap?
For years, many well-known nutritionists and trusted health sources preached against the consumption of any fat at all... Or only certain kinds of fats... Or strictly drinking olive oil upside after midnight during a lunar eclipse (okay, not quite...but you get the point). However, this widely accepted advice on fat may actually be a contributing factor to the slew of nutrition-related diseases that have become commonplace in America today.
The anti-fat position got its start in the 1960’s when Ancel Keys’ diet-heart hypothesis emerged. His theory was that saturated fat (fat from animal products, palm oil, coconut oil etc.) is the “bad fat” and that unsaturated fat (fat from avocados, olive oil, nuts, seeds, etc.) is the “good fat.” Part of the hypothesis stated that there is a direct relationship between the amount of saturated fat in a diet and the probability of coronary heart disease. Despite many clinical trials that have failed to conclusively prove this argument against fats and newer research showing fat's importance to many key body functions, incomplete information about fat continued to be widespread for years.
Is saturated fat bad?
The most current research points to no connection between saturated fats and adverse health outcomes like cardiovascular disease, heart attack, and stroke. However, more high quality research would help make these findings more conclusive.
One meta-analysis of 15 major studies found no statistically significant effects of reducing saturated fat in regard to heart attacks, strokes, or all-cause deaths. Similar reviews of dozens more studies in 2010 and 2014 similarly concluded there was no statistical correlation between consumption of saturated fat and cardiovascular disease or mortality - even among those with the highest fat intake.
Further, some research actually shows saturated fats may support many markers of good health. For example, Norwegian researchers at the University of Bergen conducted a diet intervention study analyzing the overall health of overweight individuals after subscribing to a diet high in saturated fats. They found that saturated fats did not increase the risk of cardiovascular disease and also led to substantial improvements in “several important cardio-metabolic risk factors, such as ectopic fat storage, blood pressure, blood lipids (triglycerides), insulin and blood sugar” (Ottar Nygård, Bergen professor in the Department of Clinical Science). This study, among others, incorporated one important characteristic that multiple other studies fail to consider: QUALITY!
Fat Quality is Key
Participants in the University of Bergen study mentioned above consumed high quality, minimally processed saturated fat sources, like butter, cream, and cold-pressed oils. This is key!
When it comes to fats (and food in general), it's less about unsaturated vs saturated or more vs less and more about quality. Many past studies that link fat to life-threatening health conditions use low-quality fats for testing purposes. As fats are altered through the manufacturing process using heat and chemical solvents, they can lose many of their nutritional properties, which can make it difficult for our bodies to recognize and process them. Since fat has been able to put its best, minimally-processed, high-quality foot forward in more recent nutritional studies, researchers have been able to debunk some of the misconceptions around fats and have even discovered new benefits to eating quality fats.
Benefits of Saturated Fat
Supports Brain Function
Saturated fat is the main component of brain cells, and is thus necessary for healthy brain function. In one study, it was found that people who ate more saturated fat reduced their risk for developing dementia by 36 percent.
Keeps you Nourished
Fat, and saturated fat in particular, is exceptionally nutrient dense. It's a concentrated source of energy, and helps your body feel full by slowing absorption after a meal (Mercola). Saturated fat also transports fat-soluble vitamins A, D, E, and K, facilitates conversion of carotene to vitamin A, and facilitates mineral absorption.
Strengthens Cell Membranes
Because saturated fats are solid at room temperature, they are able to strengthen our cell membranes. With too many unsaturated fats, which are liquid at room temperature, our cell membranes don’t have the structural integrity to function properly, and can become too weak to do their job. However, trans fat (found in highly processed, shelf-stable, non-organic foods) are too solid at room temperature, making our cell membranes too stiff, and are no longer recognized as safe by the FDA.
What About Unsaturated Fat?
While saturated fat hung out in detention, unsaturated fat enjoyed a positive public image that it didn’t necessarily deserve. Examples of unsaturated fats include avocados, nuts, sunflower oil, safflower oil, canola oil, fish oils, and many more. On the surface level, these foods are good for your health. But just like saturated fats, these same foods can also become harmful or lose many of their health benefits when they are subjected to a large amount of refinement and processing.
What About Trans Fats?
While saturated and unsaturated fats in their natural, minimally processed forms are typically either neutral or supportive of health, one type of fat is always detrimental: trans fats. Unlike other dietary fats, trans fats both lower your good cholesterol and raise bad cholesterol. Also called "partially hydrogenated oils," trans fats are typically formed through an industrial process that causes the oil to become solid at room temperature.
This can improve the shelf life of foods, but it turns out artificial trans fats are so unhealthy that the FDA banned food manufacturers from adding the major source of artificial trans fat to foods and beverages. The trans fat ban was enacted in 2015 with a deadline of 2018, but depending on when items were manufactured, you may still see trans fats in foods up until 2021.
Be A Sophisticated Fat Fan
So how can you enjoy the benefits of fat without the potentially detrimental effects? Focus on consuming minimally processed, high-quality fats like coconut oil, organic grass fed butter, high quality ghee, cold-pressed olive oil, avocado oil, nuts, seeds, and fatty fish. Your brain, heart, and hormones will thank you! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -