Saturated Fat, Cholesterol, and Heart Health
By Brandy Buro, RD, LD
February 15, 2022
Are you still confused about which fats help keep your heart healthy? You are not alone! For years we have been told to steer clear of saturated animal fats because they raise LDL, or "bad" cholesterol levels, and therefore increase risk for heart disease. Instead of saturated fats, we were told to use vegetable oils and margarine. However, research is proving that we’ve been misled. Let’s explore the truth about which fats are beneficial or harmful for cardiovascular health.
How Saturated Fat Got Such a Bad Reputation
Based on a "poor science" study from the 1950's, Ansel Keys hypothesized that dietary fat and cholesterol levels were linked to levels of fat and cholesterol in the blood. This hypothesis appeared to be true because he only used data from seven countries where high saturated fat was linked to higher rates of heart disease. Data from all countries did not support this connection, and they were left out of the study’s findings. Without any further studies or evidence, the American Heart Association began recommending a diet low in saturated fat and high in carbohydrates and vegetable oils for heart health. These diet recommendations have been the foundation of the American diet since the 60’s, which morphed into a diet void of good fats and high in sugary, processed foods. If Keys' research were true, this change in diet should have had a positive effect on our cholesterol levels. Instead, over twenty million Americans are on statin drugs to lower cholesterol! Something must be wrong with his theory.
The True Causes of Unhealthy Cholesterol Levels
There is no reliable research behind the message that reducing saturated fat in the diet lowers a person’s risk of unhealthy cholesterol and heart disease. A meta-analysis of twenty-one studies, published in the American Journal of Clinical Nutrition, found that "there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of coronary heart disease or cardiovascular disease."¹ Ironically, the foods that raise our cholesterol levels are the very foods we have been advised to consume—processed carbohydrates, margarine, and vegetable oils. In an article entitled, "Are Refined Carbohydrates Worse Than Saturated Fats?" Dr. Frank Hu from the Harvard Medical School said, "In this era of widespread obesity and insulin resistance, the time has come to shift the focus of the diet-heart paradigm away from restricted fat intake and toward reduced consumption of refined carbohydrates." ²
Gary Taubes examined decades of research on heart disease in his book Good Calories, Bad Calories. He concluded that cholesterol is not the cause of heart disease, but that triglycerides are a bigger part of the problem. Your triglyceride level is affected by refined carbohydrates, not saturated fats. Foods like pasta, bread, crackers, and cookies are what lead to higher triglycerides levels. When you replace processed carbohydrates with real carbohydrates, such as vegetables, and replace man-made fats with real fats such as butter, nuts, olive oil, or avocados, your cholesterol levels will begin to normalize.
At Nutritional Weight & Wellness, we have been teaching people how to lower cholesterol for years by reducing sugar and processed carbohydrates. We won’t spend too much time in this article on the refined carbohydrate connection since we want to focus on debunking the fat myth, but for more information on carbohydrates, blood sugar, and your heart health, check out this article: Balance Blood Sugars to Protect Your Heart. Now we’ll move on to what heart-healthy fats to focus on for a strong cardiovascular system and which ones to avoid.
What Fats Should You Avoid for Heart Health?
Bad fats are highly processed and include canola or rapeseed oil, soybean oil, corn oil and cottonseed oil. These oils are made using intensive mechanical and chemical processes to get the oil from the seeds. First the seed is crushed and heated; then a hexane solvent is added to get more oil out. Then the oil needs to be degummed, neutralized, bleached and deodorized. Many nutrients are removed during this process, and the oils become unstable and easily oxidized. When consumed, these refined oils can cause your cells and blood vessels to harden.
These refined oils are often hydrogenated or partially hydrogenated, a chemical process used to turn oils into solid fats like margarine or shortening. This additional processing further damages the fats. These hydrogenated fats, also known as trans fats, have been shown to increase your bad cholesterol (LDL) and lower your good cholesterol (HDL). Damaged fats also cause inflammation in the blood vessels, which contributes to the development of coronary artery disease and other chronic health conditions (3). Although trans fats were banned in 2018, damaged fats are still everywhere, even if it says 0 trans-fats on the label. Read the ingredients list and watch out for refined and hydrogenated oils. They are often found in crackers, cake mixes, baked goods, packaged foods, chips, fast food, non-dairy creamers, pastries, and bar food.
What are Good Fats for Heart Health?
Good fats are those that are found in real foods and not highly processed. These include olive oil, coconut oil, lard, butter, full-fat dairy, nuts, seeds, nut butters, avocado, and olives, as well as the fats in eggs and cold-water fatty fish. Good fats are very stable and nourishing for the body. According to Sally Fallon Morell, author of Nourishing Fats: Why We Need Animal Fats for Health and Happiness (4), one of the most important reasons we should eat foods with natural fats is for the additional nutrients they provide, like vitamin K, which helps protect our arteries and heart. Healthy fats also help us absorb more of those nutrients from food, carrying them into our cells. Good fats also help keep blood sugars stable and aid in feeling satiated. So, go ahead and add yummy butter to your broccoli!
How can you tell if it is a good fat? When you are at the store look for dark bottles and words like unrefined, extra virgin, expeller pressed, cold pressed, and first pressed. Good fats are made from things that are naturally oily, like olives and nuts (as opposed to cotton and soybeans). We recommend eating fat every time you eat. How much? Examples include 16 almonds, ½ avocado, 2 teaspoons butter or olive oil, 10 walnuts, 6 olives, 2 tablespoons cream, 2 tablespoons full fat sour cream or cream cheese, or 1-2 tablespoons nut butter.
Are Eggs Healthy?
What about eggs? Are they good for you or bad? In 2013 new cholesterol guidelines (3) were released, and in 2015 the Dietary Guidelines stated “available evidence shows no appreciable relationship between consumption of dietary cholesterol and [blood] cholesterol ... Cholesterol is not a nutrient of concern for overconsumption." (4) For many years eggs got a bad rap because there were believed to raise your cholesterol. The truth is our body makes 75 percent of our cholesterol and food contributes only 25 percent. So, enjoy eggs anytime!
Foods to Support Healthy Cholesterol Levels
The dietary guidelines for managing cholesterol and heart-health have changed over the years due to unreliable research, but we’ve returned to the fact that real food from nature does our heart the most good. If you’re worried about your cholesterol levels (or want to prevent your cholesterol levels from rising), reduce the amount of processed carbohydrates and sugar in your diet. Increase servings of vegetables while pairing it with high-quality fat to support your blood sugar and nutrient absorption. Reduce the amount of bad fats you consume (like canola or rapeseed oil, soybean oil, corn oil and cottonseed oil) and replace with natural, good fats (like olive oil, coconut oil, lard, butter, full-fat dairy, nuts, seeds, nut butters, avocado, olives). Natural fats taste delicious AND your body loves them, making it a win-win situation for you and your heart.
For more information on heart health and cholesterol, check out these resources:
- Read: Heart-Healthy Fats (and Recipes, too!)
- Listen: Heart Health Tune-Up with Dr. Steven Masley
- Listen: Diets for Cholesterol Management
- Try: CoQ10 to counteract cholesterol medications
Resources:
1) Siri-Tarino, PW, Sun Q, Hu FB, Krauss RM. Meta-Analysis of Prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. Am J Clin Nutr January 2010 ajcn.27725
2) Hu, FB. Are refined carbohydrates worse than saturated fats? Am J Clin Nutr June 2010 vol. 91 no. 6 1541-1542
3) Hu FB, Stampfer MJ, Manson JE, Rimm E, Coldtiz GA, Rosner BA, et al. Dietary fat intake and the risk of coronary heart disease in women. N Engl J Med. 1997;337(21):1491–1499.
4) Fallon, Sally. Nourishing fats: why we need animal fats for health and happiness. 1st ed. New York: Grand Central Life & Style, 2017.
5) Stone NJ, Robinson JG, Lichtenstein AH, et al. 2013 ACC/AHA guideline on the treatment of blood cholesterol to reduce atherosclerotic cardiovascular risk in adults: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 2014;63:2889-934.
6) U.S. Department of Health and Human Services and U.S. Department of Agriculture. 2015 – 2020 Dietary Guidelines for Americans. 8th Edition. December 2015. Part D. Chapter 1. Question 2.
