If you’re thinking about losing some weight in the New Year, there’s a way you can do it that’s both tasty and good for your heart. And, believe it or not, it involves eating fat. If you’re new to Women’s Health Letter, that might surprise you. And even if you’ve been reading for a while, you still might be confused about which fats you should eat. That’s simply because the subject of fats is confusing.
But here’s how you can eat fat, lose weight, and protect your heart.
Truth is, fats can contribute to weight gain or weight loss. They can be a factor in heart disease or they can protect your heart. It all depends on the type of fat you eat and how much. Fats are not your enemy as long as you get the right type in the correct amount and balance. Do this and you can lose weight and protect yourself from heart disease at the same time. Sound too good to be true? I can assure you, it’s not.
The problem is that most people are either eating too much of the wrong fats or opting for a fat-free diet. Either results in a deficiency of important essential fatty acids (EFAs) — fats your body needs but can’t make. EFAs speed up your metabolism, support your immune system, and guard against the build-up of sticky arterial plaque. Other fats have the opposite effect.
All Fats Are Not Equal
Some fats are saturated, others are unsaturated. Saturated fats are either solid or semi-solid at room temperature (butter and lard). Unsaturated fats are liquid at room temperature (most vegetable oils). Trans-fats began as oils and had hydrogen added to them (margarine and shortening), causing the oil to become either solid or semisolid. Just remember that the more solid the fat, the less protective and more harmful it tends to be.
Saturated fats are animal fats (butter, cheese, beef, pork, lamb, chicken) and some tropical oils (coconut and palm kernel). All saturated fats are not the same. They are made up of a long chain of atoms that take a longer time to burn than shorter-chained fats. The longer any fat takes to burn, the stickier it is. The stickier it is, the more likely it is to clog arteries. Small amounts are fine, but large quantities contribute to weight problems and heart disease.
Unsaturated fats: There are two types of unsaturated fats: monounsaturated and polyunsaturated. Both contain EFAs, but the polyunsaturated fats have more.
Monounsaturated fats: These are liquid at room temperature but more solid when they’re refrigerated. They include olive and canola oils, high in oleic acid, a popular monounsaturated fat. Monounsaturated fats are the only fats that lower LDL (harmful) cholesterol and raise HDL (protective) levels, so keep them in your diet. Since they’re more stable in heat than other oils, use them for stir-frying, baking, and other situations where oil is heated.
Polyunsaturated fats are liquid at any temperature and include vegetable oils, soy, fish, walnuts, pumpkin seeds, and flaxseed oil. They contain both omega-6 and omega-3 EFAs in varying ratios. The ratio of omega-6 to omega-3 fats in your diet determines how beneficial they are, so some polyunsaturated fats are better than others for your heart and weight control. EFAs are needed to make hormone-like substances, like prostaglandins, that regulate metabolism.
Trans-fats are primarily found in artificially solidified (hydrogenated) oils. These are more stable than other oils. But when oil becomes more solid, it contains less EFAs. Trans-fats are not good for you. While they lower total cholesterol, they also raise harmful cholesterol (LDL) and lower helpful cholesterol (HDL). Trans-fats also raise Lipoprotein-A, which increases your risk for heart disease. What’s more, they raise blood-sugar levels and cause more weight gain than the same amount of other fats. “Partially hydrogenated” or “hydrogenated” on a food label means the food contains trans-fatty acids (cakes, cookies, crackers, artificial cheese, and margarine). The good news is, as of June 2018, all artificial Trans fats are banished from U.S. restaurants and grocery stores. So you don’t have to worry about these anymore.
Essential Fatty Acids (EFAs)
The balance of omega-3 and omega-6 fatty acids is critical to your health. Our ancestors ate equal amounts of omega-3 and omega-6 fats, but over the last 100 years, our diets have shifted. People used to eat twice as much omega-6 to omega-3 fats (a 2:1 ratio), but we’re now eating 20:1. Omega-6 fats are essential, but too much cause blood to get thicker, stickier, and is more likely to clot. Omega-3 fats have the opposite effect. To prevent heart disease, you need more essential fats with more omega-3 and less omega-6.
Omega-3 fats are found in fish oil, flaxseed, canola oil, walnuts, pumpkins, and green leafy vegetables. Soy also contains omega-6 fatty acids, so it belongs in both categories. Populations that eat a diet high in omega-3 fats historically have a low risk for heart disease.
Omega-6 fats are found in vegetable oils like corn, safflower, sunflower, cottonseed, peanut, sesame, grape seed, borage, primrose, and soy. Omega-6 fats have protective effects only when they’re combined with sufficient omega-3 fats. Otherwise, they contribute to the stickiness in blood. Keep their amount reasonably low.
Lose Weight by Eating Fats
Dietary fats burn slowly, so a meal with fats feels satisfying. It gives energy over a long period of time — up to five or six hours. Your body contains two kinds of fats: white and brown. White fat insulates you from cold and is what you think of as “fat” when you look in the mirror. It is stored fat, used by your body for emergencies. Brown fat surrounds various organs and protects your spine, burning calories instead of storing them. Foods high in EFAs speed up your metabolism by causing brown fat to burn calories more quickly. Adding more fish, walnuts, pumpkin seeds, and flax oil in your diet can actually help you lose weight.
Keep foods containing vegetable oils (omega-6 fats) low in your diet. Israelis eat more omega-6 fats than any other population and have a high proportion of obesity. Studies show that people with low omega-3 and high omega-6 fats are likely to be both insulin-resistant (diabetic) and obese. Unheated, unprocessed vegetable oils high in omega-3 fats (like Spectrum brand) are safer. They contain a fatty acid called linoleic acid (LA) that stimulates your thyroid and increases your metabolism. LA is destroyed by heat, so use “cold-pressed” vegetable oils whenever possible and don’t heat them.
EFAs for a Healthy Heart
The number one killer of postmenopausal women is heart disease. I’m convinced that a lack of omega-3 fatty acids is one reason why. In populations where omega-3 fats are low, heart disease is high. Without enough omega-3 fats to balance omega-6 intake, you are at a higher risk for atherosclerosis, heart attacks, and cardiac arrhythmias. Studies show that people who eat more tuna have significantly less arrhythmias than those who don’t, so fresh fish isn’t required to protect your heart. When these people switched to a diet higher in animal fats, their arrhythmias worsened.
Researchers studying Eskimos in Greenland found their high-fish diet kept their blood from getting sticky and clotting, and lowered their triglycerides as well. And when postmenopausal women (some on hormone therapy, some not) were given fish oil supplements, the risk for heart disease in both groups was reduced by 27 percent. Eating fish or other foods high in EFAs, or taking supplements protects your heart.
The best diet for a healthy heart contains olive or canola oils along with foods high in omega-3 fats. You’ll get enough omega-6 fats without trying, and a little saturated fat (eggs, butter, chicken, and beef) is fine.
Eat a Mediterranean Diet
A Mediterranean diet contains olive and canola oils that raise good and lower harmful cholesterols. It’s rich in omega-3 fatty acids and includes fatty fish, walnuts, pumpkin seeds, canola oil, flax, and green leafy vegetables. Other nuts have some omega-3 fats, but not as much as walnuts. Of all vegetables, purslane, a low growing, fleshy “weed” is highest in EFAs. It’s excellent raw in salads or cooked as a side dish.
A Mediterranean diet is high in vegetable protein (beans, soy, peas, and lentils) and low in animal protein. This lowers saturated fats. Choose low-fat animal protein (lean meat, low-fat or fat-free dairy, and white-meat poultry).
Reduce or avoid vegetable oils high in omega-6 fats (corn, soy, sunflower, and safflower) and trans-fats (cookies, crackers, cakes, chips, and many convenience foods). And of course, avoid deep-fried foods.
The American Heart Association suggests eating two, three-ounce servings or more of fatty fish each week, the more the better. Some fatty fish include: catfish, halibut, herring, lake trout, mackerel, pompano, salmon, striped sea bass, albacore tuna, and whitefish.
One note: it’s important to know that all salmon is not alike. Farmed salmon has less omega-3 fats than wild salmon, because they are fed soybean oil in their diet, rather than the high omega-3 oils found naturally in algae. Most restaurants serve farmed salmon, and farmed salmon has the highest antibiotic residue of any animal-based protein, according to fats and oil expert, Mary G. Enig, PhD. Whenever possible, choose salmon that has been frozen at sea (FAS).
Good Quality Fish Oil Supplements
Instead of eating more fish, some people prefer taking supplements. A recent evaluation of 19 different brands of fish oil capsules concluded that one-third of the products tested did not have the amount of active ingredients they claimed to have.
The following brands contained the amount of DHA and EPA they claimed: Health from the Sun, Jarrow, Member’s Mark, Pure Encapsulations, Puritan’s Pride, Shaklee, Solgar Omega-3, Spectrum, The Vitamin Shoppe, Trader Darwin’s, Vitamin World, and ZonePerfect. Nature’s Way Neuromins, which is an algae product containing only DHA, also passed this evaluation. None of the tested products contained mercury.
How Much Do You Need?
The type of EFAs found in fish oils differs from those in vegetable sources, and both are important. The EFAs in fish oils are particularly protective, so I suggest you either eat fish three times a week or take daily fish oil supplements. If you’re a vegetarian who objects to this, increase your vegetable sources. Personally, I find the research on the benefits of fish oils so compelling that I do take fish oil supplements daily, although I consider myself a vegetarian and don’t eat fish.
To protect yourself against heart disease, I suggest that you get about one gram of fish or flax oil a day. If you have high blood pressure, high triglycerides, or other signs of heart disease, three to five grams may be more helpful. For weight control, take two to three grams a day. One tablespoon of flax oil equals one gram. Talk with your doctor or pharmacist if you’re taking medications to make sure there are no negative interactions. Fish oils thin the blood just like aspirin, gingko biloba, and garlic. You don’t want to thin your blood so much that it causes bleeding.
For more information on fats and oils, most people turn to Fats & Oils by Udo Erasmus. I prefer the new book by Mary G. Enig, PhD, Know Your Fats. Dr. Enig is a nutritionist and biochemist known for her expertise in this area. While I disagree with her position on soy (she says it’s harmful, I and my respected colleagues say it’s beneficial and safe), I think she knows more about the subject of fats than any other writer or researcher.
Ideas to Add Good Fat to Your Diet
While it’s important to reduce foods high in both saturated fats and heated vegetable oils, it’s just as important to eat more foods with essential fats. Here are a few ideas on how to add good fats to your diet: add a few walnuts or pumpkin seeds to your cereal, salads, and vegetable dishes. Eat more fish, soy, and beans and less chicken and beef. Buy eggs that say they are high in Omega-3. Add flax oil to salad dressings and use it on steamed vegetables or potatoes. For delicious recipes that emphasize omega-3 fats, see Ann Louise Gittleman’s book, Eat Fat, Lose Weight Cookbook (Keats Publishing, 2001).
• Fat-free or very low-fat diets are not the answer
• Reduce animal fats
• Reduce the consumption of all heated vegetable oils
• Use small amounts of canola and olive oils
• Eat more fish, walnuts, green vegetables, and flax
• Add omega-3 supplements to your diet (fish oil, borage seed oil, evening primrose oil)
Enig, Mary G., PhD. Know Your Fats, Bethesda Press, 2000.
Enig, Mary G., PhD. Know Your Fats, Bethesda Press, 2000., www.knowyourfats.com.
Simopoulos, A.P. “Essential fatty acids in health and chronic disease,” American Journal of Clinical Nutrition, September 1999.
Storlien, L.H., et al. “Fish oil prevents insulin resistance induced by high-fat feeding in rats,” Science, vol. 237, 1987.
U.S. Department of Agriculture, Agricultural Research Service, 2001.
Walsh, G.P. “Dietary change and coronary heart disease,” Medical Hypotheses, vol. 31, no. 2, February 2000.