The truth about fats
by Cherie Calbom, M.S.
This article was originally published in October 2010
We’ve survived the era of low-fat diets and learned about the health problems they create, but the media still attempts to guide our thinking that fats can make us fat and cholesterol causes heart disease.
The truth is that fats play an important role in our body’s health and some of them can even help us lose weight. Unfortunately, we consume too few of the healthy fats, and too many of the unhealthy, man-made versions.
The roles fats play in our health are extensive. For example, fat provides energy; it’s difficult to eat enough food on a low-fat diet to get the energy we need. Essential fatty acids are brain food — a deficiency can lead to numerous health and psychiatric/social problems. Fats are needed to absorb fat-soluble vitamins such as A, D, E and K. Fats give us a feeling of satiety, preventing hunger soon after meals.
Big fat misconception
Saturated fats were the preferred choice until the mid-20th century. Then, all of a sudden, we were told to cut saturated fats from our diet if we wanted to maintain healthy weight, have good cholesterol, and prevent heart disease. Marketers of low-fat foods championed the cause and few people questioned why foods eaten for centuries suddenly were causing heart disease.
It’s interesting that at the turn of the last century, saturated fats such as coconut oil were advertised as healthy. Saturated fats even were recommended for treating serious medical conditions, such as tuberculosis and epilepsy.
While medical experts claimed “fats are good” prior to World War II, we heard just the opposite in the years that followed, once the vegetable and seed oil industry stepped up production because tropical oils couldn’t be shipped during World War II.
But drastically reducing fats from the modern diet has not solved our heart health or weight problems. Statistics show that obesity rates are at an all-time high as is heart disease, cancer, diabetes and stroke.
A study published in 2006 in the “Journal of the American Medical Association” found virtually identical rates of heart attack, stroke and other cardiovascular disease in women who did or didn’t follow a low-fat diet. Women on the low-fat diet also didn’t lose — or gain — any more weight than women who followed their usual diets. The doctrine of low-fat eating has lost credibility.
What’s theory, what’s fact?
The anti-saturated fat theory began in the 1950s with the steep rise in heart disease. While heart disease caused no more than 10 percent of all deaths in the United States prior to the 1920s, by the 1950s it had risen to more than 30 percent. Researchers began looking for the cause of this new health threat and targeted cholesterol as the culprit.
Many researchers, however, have rejected the saturated fat and cholesterol theory as a cause of heart disease because more than 60 percent of all heart attacks occur in people with normal cholesterol levels and the majority of people with high cholesterol levels never have heart attacks. A study published in August 2010 in the “American Journal of Clinical Nutrition” found that if saturated fat in the diet is too low, it can lead to an increased risk of death from stroke.
Another fat, however, is being implicated in poor health. A study conducted at the Wynn Institute for Metabolic Research in London examined the composition of human aortic plaques. It found that the artery-clogging fats in those who died from heart disease were composed of 26 percent saturated fat and 74 percent polyunsaturated fatty acids.
The researchers determined no association with saturated fats but rather implicated polyunsaturates, such as those found in vegetable oils, as the primary contributors to aortic plaque formation and suggested that people avoid these oils completely.
The American Heart Association has discovered that people with heart disease all have one thing in common — inflammation. High cholesterol levels are not even on the list.
Researchers currently are focusing on damaged fats (particularly trans fats found in margarine, snack foods and fried foods), the use of oils high in omega-6 fatty acids (polyunsaturates), inflammation, blood clots, high blood pressure, high levels of homocysteine (an amino acid in the blood), and high levels of Lp(a), a protein produced in the liver. When Lp(a) encounters an LDL cholesterol particle (“bad” cholesterol”), it binds to it and confers a much more aggressive behavior to the LDL particle.
It may be surprising that saturated fats now are considered the healthiest fats for cooking precisely because they are saturated. There are no double bonds between the carbon atoms; they’re fully saturated with hydrogen atoms. This structure means that bonds will not break easily when heated and saturated with oxygen.
By contrast, unsaturated fats, such as olive and canola oil (monounsaturated fats) and safflower, sunflower, soy, and corn oil (polyunsaturates) have carbon bonds that are not saturated. Their double bonds can become saturated with oxygen from the environment. When this happens, the oils have oxidized and become rancid and unsuitable for consumption. This happens easily with these oils and can occur even in their processing.
The healthiest fats and oils
- Butter is a saturated fat dominated by short-and medium-chain fatty acids. It’s a healthier choice than margarine or most vegetable spreads, with the exception of coconut oil and olive oil spreads. Butter is a rich source of vitamins A, E, K and D. It also has appreciable amounts of butyric acid, used by the colon as an energy source, and lauric acid, a medium-chain fatty acid, which is a potent antimicrobial and antifungal substance.
Butter from grass-fed cows also contains conjugated linoleic acid, which protects against cancer. (Look for Organic Valley’s Organic Pastured Butter at PCC.) Butter is good for medium-heat cooking with a smoke point of 350° F. Ghee (clarified butter) has a smoke point between 375° F and 485° F and is good for medium-to high-heat cooking.
- Extra-virgin olive oil is a monounsaturated oil that’s great for salad dressings, cold foods, and low-heat cooking. Spectrum’s smoke point is 325° F. Other monounsaturated oils, such as Spectrum’s avocado (smoke point 450° F) and almond oil (smoke point 495° F) are better suited for higher-heat cooking.
- Coconut and palm oil are saturated fats. Coconut oil is great for low- or medium-heat cooking (smoke point 280° F to 350° F, depending on brand). Palm oil is good for higher-heat cooking (smoke point 450° F).
These oils won’t oxidize (turn rancid) as easily because they’re saturated and have a longer shelf life than most oils. Coconut and palm oil are dominated by medium-chain triglycerides, which use up energy when metabolized. They have a “thermogenic effect,” meaning they raise body temperature, boosting energy and metabolic rate, promoting weight loss. They have no cholesterol and have not been shown to raise LDL levels. Coconut oil tastes great on popcorn, too.
- Essential fatty acids (EFAs) are the “good fats” that everyone needs to maintain optimal health. EFAs are long-chain polyunsaturated fatty acids, which include linolenic (omega-3) and linoleic (omega-6).
During the past half century the ratio of omega-6s to omega-3s in the Western diet has changed from 2:1 to as much as 25:1. Our diets now include too many oils rich in omega-6s (corn, safflower, sunflower, cottonseed, peanut and soybean oils), and too few omega-3s, which are found primarily in fish, fish oil and seafood; grass-fed meat and dairy; walnuts; and flax, hemp, and chia seeds and in smaller amounts in vegetables, whole grains and beans.
Oils and fats to limit/avoid
- Polyunsaturated oils such as corn, soy, safflower and sunflower oils are hard-seed oils high in omega-6s and should be limited or avoided if possible. (Safflower and sunflower oils labeled high-heat or high oleic are exceptions — they’re primarily monounsaturated.) Polyunsaturates have more than one double bond, which break easily, and makes them more vulnerable to oxidation and degeneration. Oxidized oils can cause widespread free-radical damage, implicated in heart disease and cancer.
Vegetable- and seed-based oils have been around for less than 100 years and their rise in popularity in the 1950s paralleled a drastic increase in heart disease. Traditionally bred high-oleic versions of safflower or sunflower oils are one option for high-heat cooking but almond oil, avocado oil and ghee are better choices. Most soy and corn oils also are from genetically modified (GM) crops.
- Canola oil is a monounsaturated fat, like olive oil, which means it contains only one double bond. So, technically, it could be used for salad dressings, cold foods, and low-temperature cooking. Unless it’s organic, assume canola oil is made from GMO canola.
- Trans fats are created in the process of hydrogenating oils and should be avoided completely. The consumption of trans fats increases the risk of coronary heart disease by raising levels of LDL cholesterol and lowering levels of HDL (“good”) cholesterol. Commercially baked goods, such as crackers, cookies, cakes, muffins and many fried foods, such as doughnuts and French fries, may contain trans fats. Mainstream shortenings and margarines can be high in trans fat.
- Margarine and butter replacement spreads. Margarine is made from different oils mixed with emulsifiers, vitamins, coloring, flavoring and other ingredients. The oils often are hydrogenated — a process used to solidify them, making the margarine spreadable.
A report by Harvard researchers says trans fat in margarine and other processed foods could be responsible for thousands of the nation’s annual deaths from heart disease. When it comes to natural spreads that are substitutes for butter, read labels; know what oils are used. An olive oil spread would be fine but anything made with polyunsaturates or non-organic canola oil should be avoided.
Cherie Calbom, M.S., has a master’s degree in nutrition from Bastyr University, where she now serves on the Board of Regents. She is the author of 17 books on nutrition, including “The Coconut Diet” and “The Juice Lady’s Turbo Diet.” For more information, see cheriecalbom.com.
- Howard BV, Van Horn L, Hsia J, et al. Low-fat dietary pattern and risk of cardiovascular disease: the Women’s Health Initiative Randomized Controlled Dietary Modification Trial. JAMA. 2006; 295:655-66.
- Yamagishi, K, Iso H,Yatsuya H, et al. Dietary intake of saturated fatty acids and mortality from cardiovascular disease in Japanese: the Japan Collaborative Cohort Study for Evaluation of Cancer Risk Study. American Journal of Clinical Nutrition. 2010 August 4.
- Felton CV, Crook D, Davies MJ, Oliver MF. Dietary polyunsaturated fatty acids and composition of human aortic plaques. Lancet. 1994 October 29; 344(8931):1195-6.
- Fat in Margarine Is Tied to Heart Problems. The New York Times. 1994 May 16.