When it comes to weight loss, much of what we see in the public talks about avoiding fat. However, fat is a crucial part of our body chemistry and avoiding it altogether may not be necessary once you figure which fats are your friends. This is the second of a three-part series by Jette R. Hogenmiller, PhD, MN, APRN.
The information contained in this article should not be construed as medical advice. Consult your health care provider for appropriate diet changes for you.
What are Fats?
There are three major macronutrients that make up what we eat: carbohydrates, proteins and fats. In the first article of this three-part series on Struggling with Weight, we focused on your body’s difficulty in breaking down processed foods. In fact, these chemicals can be counterproductive to losing weight. This second article will help you select fats that support health and your long-term weight goals. We want to provide you with a basic chemistry lesson to help you grasp which fats are your friends and which are not. The recommendations may surprise you. The core of the matter is we do not eat enough fat. Specifically, we do not eat adequate healthy fats. Regardless of what you learn, we recommend you discuss any changes in your diet with your health care provider to assure the recommendations are appropriate for you.
Hang in there as we walk you through some chemistry to better understand why the type of fats and oils we eat affect our health. If you flunked chemistry, you can skip to the end to help create next week’s grocery list, but if you want to know why, dig in.
There are many types of fats (lipids): fatty acids, phospholipids, sphingolipids, sphingomyelins and steroids (e.g. cholesterol). We need to focus on fatty acids, as their make-up determines the impact of oils (liquid) or fats (solid) on health.
A Hardcore Chemistry Lesson on Carbon Chains & Double Bonding
The number of carbon atoms determines whether a fatty acid is considered a short (~8-10), medium (~10-20) and long-chain (~14-24) fatty acid.
Fatty acids are also identified as saturated or unsaturated (mono or poly). Saturated means there are only single bonds in the carbon chain (-C-C-). Monounsaturated means one (1) carbon has a double bond (-C=C-), so there are fewer other molecules such as hydrogen attached to the carbon molecules. A polyunsaturated fatty acid has more than one (1) carbon with a double bond
Double bonds like those seen in polyunsaturated fatty acids result in more curvature of the structure. The curvature makes it harder to bend, whereby they are more likely to remain in the liquid, oil, form. In contrast, saturated fats with single bonds easily bend and are therefore prone to the solid, fat, form.
The presence of double bonds provides for increased likelihood of interaction that can include normal metabolism or result in fats becoming rancid (spoil). These double bonds can be located on different carbons. When the double bond is on the third carbon it is a 3-omega fatty acid, and when it is on the sixth carbon it is a 6-omega fatty acid.
What Does All that Mean to Cooks in the Kitchen?
Whether a fat is a saturated or unsaturated fat/oil, there are health implications. Saturated fats are very stable because all the carbons have single bonds. They do not become “rancid” or go “bad” easily. They include such things as animal fats and tropical oils. Because they are very stable they are less reactive with other molecules, therefore less inflammatory. It is also important to know that animal fats are actually not primarily saturated, but a mixture. For example, beef, lard and chicken fat are respectively 54, 60 and 70 percent unsaturated.
Monounsaturated fats are also relatively stable, not as reactive as polyunsaturated fatty acids. They also do not go rancid easily. They include such oils as olive oil and oils from almonds, pecans, cashews and peanuts. We are all aware of the Mediterranean diet, including the use of olive oil, reinforcing that saturated fats are not inherently bad for us.
Polyunsaturated fats such as corn oil and flax, fish and other oils are relatively unstable. They should not be heated as they can form unhealthy trans fats. It turns out that when we transitioned from use of animal fat to corn oil for French fries, they become unhealthier as more of the fat becomes absorbed into the potato and trans fats occur when the oil is heated. The “old” fries were actually less harmful.
Sandage and Bull (2012) point out, “Eating foods that contain rancid oils increases free radical activity that speeds aging, causes inflammation, and causes disease.” (p. 25). Enig (2010) explains that the food industry turns naturally liquid fats, such as corn oil, into solids. This makes the food less greasy and easier to shape, for example, into a cookie. This is done by a process called “partial hydrogenation.” She goes on to say, “These plastic, man-made fats are usually much firmer than the natural baking fats like lard and palm oil, and the baker can pack more of this fat into the product without producing a greasy feel”(p. 20). The resulting fat is more saturated than the original fats we used to use.
This process increases the shelf-life of a product, but can produce trans fats that are worse for our health by increasing the hardening of the arteries (atherosclerosis). There is actually thought that excessive intake of trans fatty acids by a pregnant woman can cause developmental problems in a child (Haas, 2006) as they can cross the placenta and into breast milk.
How Fats Help us Stay Healthy
Adequate fat intake is important for health. Fats (9 calories/gm) provide for more energy, more than twice per gram than carbohydrates (4 cal/gm) or proteins (4 cal/gm). Fats are needed for growth of blood vessels and nerves. Fats provide the ability for communication along nerve cells. Fats provide lubrication for skin and other tissues. Fat is important for growth spurts, hormone production and even helping the immune system fight infections.
Fats also have many other positive effects on the body. They are needed to absorb fat-soluble vitamins A, D, E and K, and they provide for slow absorption of foods so we feel fuller for a longer period of time. Fats also make food taste good.
The Ideal Ratio of Carbohydrates, Proteins & Fats in Your Diet
If you read five different sources of how much fat, carbohydrates and protein you should consume, you will likely get five different recommendations. While there certainly is room for a range of percentages of these macronutrients, the Nutrition Therapy Association says “healthy fatty acid deficiency is epidemic” (2004). We have gone to such extremes in reducing fats, our bodies do not have enough healthy fats and the fats we are eating actually make our health worse and foster weight gain. This is because we eat more of other calories while trying to satisfy the needs of our body due to the missing fats.
Anji Sandage and Lorena Bull (2012) make an important statement when they say, “Probably the most common mistake in dieting is eating a ‘healthy’ low-fat diet. It is possible to lose weight this way; however, very few people are able to do so and keep the weight off because the lack of dietary fat causes carbohydrate cravings that undermine the diet process” (p. 15).
Which Fats to Avoid & Which to Use
Let’s talk about omega-6 and omega-3 fats. The key here is the balance.
We can find omega-6 in such fats/oils as canola, corn, peanut, poppy seed, safflower, sesame, soy, sunflower, walnut, oat germ, wheat germ and rice bran. It turns out that peanuts are high in omega-6 and you should eat them in moderation, while increasing omega-3-rich foods such as sesame seeds, walnuts, flaxseeds, and pumpkin seeds.
Omega-3 is found in flaxseed, flax oil, chia seed, pumpkin seed, and are also found in cold-water fish such as mackerel, trout, cod, halibut, and salmon.
Currently, we eat approximately 10 to 20 times more omega-6 fats than omega-3 fats (Haas, 2006). This is a problem, as the best balance would be 1:1 or up to 4:1 ratio. Experts believe that when there is an excessive amount of omega-6 to omega-3, it increases the risk for chronic inflammation, type 2 diabetes, coronary heart disease and other illnesses (Haas, 2006). Omega-3 has also been “proven to regulate appetite and to accelerate fat burning – beneficial when trying to lose weight,” according to Kennedy and Reno (2009, p. 152).
It may be time to rethink canola oil, or develop a new approach to its use. It turns out that canola oil is a variety of rapeseed. Rapeseed oil has 40 to 50 percent erucic acid, a very long-chain monounsaturated fatty acid that was found not to be good for human consumption. Creators developed canola oil through genetic engineering via recombinant DNA. Dr. Weil’s Guide to Women’s Health Over 40 (2012), included expeller-pressed canola oil in his “anti-inflammatory food pyramid.” There is some controversy over whether canola oil should be part of a healthy diet. Fallon and Enig (2001) state, “There are some indications that canola oil presents dangers of its own. It has high sulphur content and goes rancid easily. Baked goods made from canola oil develop mold very quickly. During the deodorizing process, the omega-3 fatty acids of processed canola oil are transformed into trans fatty acids, similar to those in margarine and possibly more dangerous” (pg. 19-20). We recommend, when using canola oil, not to use it for a recipe that includes heating it, but rather cold and as indicated, expeller-pressed. This process generally provides for obtaining the oil through pressure rather than heat.
Coconut oil, although it is primarily a saturated fat, is a healthy fat. It is a medium chain triglyceride (MCT) fatty acid. The advantage in this is you can use coconut can quickly for energy, generally not ending up as fatty tissue; some experts also identified it as having a positive effect on health (Fife, 2004). Coconut oil goes directly to the liver and the body burns it for energy. The oil tolerates high temperatures, so you can use it to fry food. Experts also identified this tropical oil as having antifungal and antimicrobial properties (Fallon & Enig, 2001).
Eggs can be tasty when fried in coconut oil, and cooks can substitute coconut oil for corn oil when changing a recipe to make it healthier. Another option is to use coconut oil as a substitution for fats in an “eat-clean” blueberry muffin with a sugar cane topping. You can use it in recipes to replace corn oil or other fats on a 1:1 basis. You can also melt it in the microwave to make for easier use in a recipe calling for liquid oil. Two tablespoons per day of coconut oil is recommended. The book “The Coconut Oil Miracle” by B. Fife has a collection of coconut-based recipes.
There are also “eat-clean cookbooks” that address specific dietary recommendations for men. One such book is R. Kennedy and T. Reno’s: “The Eat-Clean Diet for Men – Your Ironclad Plan to a Lean Physique” (2009). While we do not agree with all aspects of the book, it very directly addresses nutrition in men and the effect on sexual functioning.
Bad friends: Avoid/Limit/Do not eat
- Corn oil
- Partially hydrogenated/hydrogenated – those that have been artificially made through food processing
- Avoid fresh water fish (cat, carp) (Fallon & Enig, 2001) unless confident about lack of contamination
Good friends: Eat/include 30 percent fat or no less than 15 percent (Kennedy) of daily dietary caloric intake, for weight and height. The below are consistent with healthy fats:
- Olive oil, extra virgin; if non extra-virgin oil do not cook with it, as it cannot tolerate temperatures as high as extra-virgin olive oil can
- Coconut oil – organic, extra-virgin, cold press extracted without additives
- Walnuts, safflower, sesame, sunflower, almond, flaxseed
- Flaxseed – 4 tablespoons daily with meals; store in refry; grind in coffee grinder
- Meats that were grass fed, not grain/corn fed
- Fish, 7-10 ounces per week – cold-water (e.g. wild salmon, trout). Often wild caught fish have more omega-3 fats than farm raised. It is suggested to avoid shoreline fish, as there may be a risk of increased mercury. Small amounts of mercury in some fish are normal.
Eat in a limited manner
- Canola oil – if used, use expeller-pressed and avoid heating.
- Peanut oil – limit the amount due to the high omega-6 and need to avoid imbalance of 6 to 3-omega fatty acids.
We also recommend the advice of Sandage and Bull (2012), “Dump the fake fats: margarine, Crisco, and processed vegetable oils. Get the ones that actually taste good: coconut oil, ghee, butter, and rendered animal fats” (pg. 16).
In May, we will continue our “Struggling with Weight” series and talk about the problem with sugar.
Jette R. Hogenmiller, PhD, MN, APRN.
Enig, M.G. (2010) Know Your Fats: The Complete Primer for Understanding the Nutrition of Fats, Oils and Cholesterol. Bethesda Press, Bethesda, MD.
Fallon, S, Enig, M.G. (2001). Nourishing Traditions: The Cookbook that Challenges Politically Correct Nutrition and the Diet Dictocrats. New Trends Publishing Inc. Washington, D.C.
Fife, B. (2004). The Coconut Oil Miracle (Previously published as The Healing Miracle of Coconut Oil). Penguin Group, Inc. New York.
Kennedy, R & Reno, T. (2009) The Eat-Clean Diet for Men: Your Ironclad Plan for a Lean Physique! Robert Kennedy Publishing. Ontario, Canada.
Sandage, A., Bull, L. N. (2012). The Everything Coconut Diet Cookbook. Adams, Media. Avon, MA.
Weil, A. (2012). Dr. Andrew Weil’s Guide to Women’s Health Over 40.