Redefining Fats in our Diet
Fats in our diet are often thought of as something negative. After all, the definition of fat in the Merriam Webster dictionary includes words like "plump, oily, and greasy, none of which sound very appetizing.
Therefore, many of us believe that eating healthy involves buying low fat foods, counting fat grams, eating less red meat, and eating "heart-healthy" margarine instead of butter. We have been brain-washed to believe that fats cause us to be fat, that unsaturated fats are "good fats" and saturated fats are "bad fats", and are often reminded that we should cut back on animal foods including eggs, milk, and meat in order to keep cholesterol levels low. This way of thinking is harmful because in order to function properly, our body needs fat, including cholesterol.
But training our mind to change the way we think about fats is difficult, especially since both the American Heart Association (AHA) and the United States Department of Agriculture (USDA) advocate a low-fat diet low in saturated fats and high in polyunsaturated fats. In addition, the junk food industry, manufacturers of cholesterol-lowering drugs, and the media have done an amazing job convincing us that fats in general are bad for us.
Despite all this, statistics are proving the contrary. Three common myths about fats are currently being debunked by leading health experts.
Myth 1. Lowfat diets prevent obesity and other degenerative diseases.
We have been told this for years. That if we minimize our fat intake we'll live long, healthy lives. So for decades, many bought into this fat-free frenzy in fear of falling victim to obesity and other diseases. This resulted in a profitable market of over 15,000 low-fat products filled with sugar, artificial flavorings, and other additives to make up for the lack of taste after the fat was removed.
You would think that after years of avoiding fat, we would be one of the healthiest nations on earth. Wrong! It turns out that the rate of obesity and heart disease has increased rather than gone down. People are gaining weight despite their attempt to eliminate fat. This in turn leads to frustration and a continual search for additional ways to lose pounds.
In the article, "Taking the fear out of eating fat", which was published in the Weston A. Price Foundation quarterly newsletter, author Lori Lipinski mentions that clients of hers who eat low-fat diets are often very unhealthy and suffer from symptoms of depression, anxiety, mood swings, insulin resistance, digestive disorders, hormone imbalances, loss of hair, and dry, wrinkly skin. Yet these same clients still believe that continuing to avoid fat will make them healthier. [1]
There are a couple reasons why low-fat diets could cause people to become unhealthy and gain weight. It is true that fat contains more calories (9 calories per gram) than carbohydrates (4 calories per gram), however it sends signals to the brain that tell you to stop eating, fills you up, and provides you with long-lasting energy throughout the day, which in turn minimizes food cravings. Low-fat, high-carb foods on the other hand usually do not satisfy your hunger, which can lead to eating more. A high-carb diet also raises insulin levels, which increases inflammation in your body and stores excess glucose as fat. And finally, eating low-fat, high-sugar foods may cause us to "crash and burn", leaving us feeling fatigued with no energy to burn off calories.
Myth 2. Polyunsaturated omega-6 vegetable oils are "good" heart-healthy fats and better than saturated fats.
We have been convinced that consuming vegetable oils and "heart-healthy" margarine are good for our heart and certainly much better than saturated fats. Both the American Heart Association and the government have repeatedly informed us of this. The AHA states that one of the goals of healthy eating is to "Use liquid vegetable oils such as olive, canola, corn or safflower as your main kitchen fat" and to "use liquid vegetable oils in place of solid fats" [2]. The USDA informs us to "Consume less than 10 percent of calories from saturated fatty acids by replacing them with monounsaturated and polyunsaturated fatty acids" [3]. While it is true that most monounsaturated fats, including olive oil, are very healthy, studies are contradicting some of the hype about polyunsaturated fatty acids (PUFAs).
Recently, after recovered data from the Sydney Heart Study was evaluated to determine the effectiveness of replacing dietary fat (from animal fats and shortening) with omega-6 polyunsaturated fats (from safflower oil and margarine) for the secondary prevention of heart disease and death, no clinical benefits were found. Rather instead, it was concluded that the substitution of dietary polyunsaturated fats in place of saturated fats actually increased the rates of death from all causes, coronary heart disease, and cardiovascular disease. In addition, an updated meta-analysis of these omega-6 fat intervention trials showed no proof of cardiovascular benefit [4].
Unsaturated fats include both monounsaturated and polyunsaturated fats. Our body makes monounsaturated fats from saturated fatty acids. They contain one double bond between two carbon atoms with a kink or bend at this position. This disables them from packing together as easily as saturated fats, which results in them being liquid at room temperature. They are relatively stable and do not go rancid easily so they can be used when cooking with low heat. Common sources include olive oil, avocados, and some nut oils including almond, pecans, and cashews.
Polyunsaturated fats, on the other hand, are comprised of two or more pairs of double bonds, which are also bent. This results in them being liquid even at room temperature. They are highly unstable and go rancid easily so they should never be heated or used in cooking. Unlike monounsaturated fats, these fats are "essential" since our body cannot make them and should, therefore, be obtained from our diet. The two most common types of polyunsaturated fats include omega-3 and omega-6 fatty acids. Omega-3 fats include fish oils and flaxseed, and omega-6 fats include vegetable oils such as canola, sunflower, safflower, corn, and soy oils. Omega-6 is pro-inflammatory and omega-3 is anti-inflammatory. While acute inflammation is needed to heal our bodies from injuries, too much becomes chronic and causes more harm than good. Contrary to being "heart-healthy", omega-6 vegetable oils should be avoided or reduced for several reasons:
1. Too much omega-6 in relation to omega-3 causes chronic inflammation.
Vegetable oils contain high amounts of omega-6 fatty acids. The ideal ratio of omega-6 fats to omega-3 fats is anywhere from 1:1 to 4:1, which was the case prior to the industrial revolution. Unfortunately, since then, due to the addition of vegetable oils in processed foods, consumption of omega-6 fats have steadily increased, resulting in a ratio of about 16:1 on average, and reaches up to 25:1 in some people [5].
This increase in omega-6 versus omega-3 fatty acids has resulted in an increase in inflammatory diseases, including heart disease [6]. One study concluded that the risk of heart disease was significantly higher in omega-6 specific diets compared to mixed omega-3/omega-6 diets and stated that "advice to specifically increase n-6 specific PUFA (omega-6 fatty acids) intake ... is unlikely to provide the intended benefits, and may actually increase the risks of CHD and death" [7].
2. Vegetable oils are easily oxidized.
PUFAs are very chemically unstable and highly susceptible to being damaged. Exposure to air, light, and especially high temperatures cause them to oxidize and go rancid. This is why vegetable oils go bad after only a few months on the shelf.
Refined vegetable oils already start off damaged since extremely high heat is used during the process of extracting oil from the seed. This renders them defenseless against future oxidation during storage and cooking. The seeds contain antioxidants that possibly could help fight this damage, however they are also destroyed in this process.
Oxidized fats that are consumed in excess are incorporated into our cell membranes and can cause destructive oxidative chain reactions to other cells and structures, including DNA/RNA and blood vessels. This in turn can lead to all sorts of health issues, including liver damage, premature aging, and cancer [8].
3. Vegetable oils are far from natural.
First of all, most vegetable oils, including almost all soy, corn, AND canola oil, are genetically modified. As if this alone isn't enough, they are manufactured in factories with the help of high temperatures and chemicals that strip away anything natural. They are first pressed, crushed, heated, and bathed in solvents made from crude petroleum. After this they are bleached and steamed in temperatures over 500 degrees Fahrenheit to remove any unpleasant colors or odors. And finally, some manufacturers in the U.S. add the preservatives BHT and BHA to prevent rancidity. This differs quite a bit from saturated fats such as beef fat, lard, and coconut oil, which are naturally stable and unprocessed.
In addition, vegetable oils are turned into margarine through a process called hydrogenation, which unnaturally makes liquid oils solid by adding hydrogen. Thus the term "hydrogenated oil", better known as "trans fat", was created.
Myth 3. Saturated fats are "bad" fats that increase cholesterol levels.
Saturated fats have been classified in the "bad" fat category along with trans fats, which truly are bad for you, for way too long. According to the American Heart Association, "Eating foods that contain saturated fats raises the level of cholesterol in your blood" and "high levels of blood cholesterol increase your risk of heart disease and stroke" [9].
Before reading on, erase everything you've previously learned about saturated fats. Just because they are called "saturated" does not mean they are "bad" fats. Saturated simply means that the carbon atoms in a fatty acid chain are "saturated " with hydrogen atoms, leaving no room for double bonds. This results in it being chemically stable (unlike the unstable polyunsaturated fats). It has nothing to do with clogging arteries.
In fact, a meta-analysis evaluating the association of saturated fat with heart disease, which was published in the American Journal of Clinical Nutrition in 2010, proves this point. After reviewing 21 studies, it was concluded that there is no significant evidence that dietary saturated fat is associated with an increased risk of cardiovascular disease [10].
It is also interesting to note that although certain tribes in Africa consume diets consisting of 65% saturated fat and high amounts of cholesterol through red meat and dairy, they have some of the lowest rates of heart disease. Likewise, the Eskimos have very low rates of heart disease despite the fact that their diet consists of 75% saturated fats from whale blubber [11].
Saturated fats and cholesterol are essential for many reasons. They
provide a concentrated source of energy.
are an integral part of cell membranes and structures.
help us go longer without feeling hungry by slowing down absorption.
act as carriers for important fat-soluble vitamins including A, D, E, and K.
help to convert sunlight into vitamin D.
are essential for synthesizing a number of hormones including our stress hormones and the sex hormones testosterone, progesterone, and estrogen.
are used by the liver to make bile, which is needed to digest fats.
help maintain the integrity of the intestinal wall and protect us from pathogens in the digestive tract.
At least 50% of our cell membranes are composed of saturated fats so it makes sense that the majority of the fats in the diet are also saturated. Together with cholesterol, these fats give our cells stiffness and stability. Polyunsaturated fatty acids on the other hand, if eaten in excess, tends to replace the saturated fatty acids and cause the cell membrane to become flabby. One theory explaining why blood cholesterol levels decrease temporarily when saturated fats are replaced with polyunsaturated ones is that cholesterol from the blood is moved to the tissues in order to once again restore their structural integrity [12].
In a review published in the journal Advances in Nutrition, Dr. Glen D. Lawrence from the Long Island University states, "Although early studies showed that saturated fat diets with very low levels of PUFAs increase serum cholesterol ..., the evidence of dietary saturated fats increasing coronary artery disease or causing premature death was weak." He further states that recent analyses indicate that saturated fatty acid, especially in dairy products and coconut oil, can improve health and that "the replacement of saturated fats in the diet with carbohydrates, especially sugars, has resulted in increased obesity and its associated health complications [13]."
When eating saturated fats from animals, it is important to eat GRASS-FED animals vs grain-fed. According to the Westin A. Price Foundation, grass-fed beef fat contains a total of 45% less total polyunsaturated fats, including 66% less omega-6 fatty acids. In addition, it also contains 4 times MORE omega-3 fatty acids [14]. So eating grain-fed animal fats may raise the already large ratio of omega-6 to omega-3 fats in our diet, which again, may cause chronic inflammation.
The Bottom Line
For years we have been told to eat "heart-healthy" vegetable oils and margarine, and avoid saturated, artery-clogging fats. Yet the opposite is true. We actually want to enjoy good quality, natural fats and avoid chemically processed, unnatural, inflammatory ones.
To sum it up:
Eat saturated fat from grass-fed beef, butter (rich source of fat-soluble vitamins A,D,E, and F), and coconut oil (strong antifungal and antimicrobial properties)
Use lard (pork fat), tallow (beef fat), ghee (clarified butter), butter, and coconut oil (great for high temperatures) to cook with.
Enjoy high quality extra-virgin olive oil drizzled over salads or with low heat as it is unstable in very high temperatures.
Eat omega-3 fatty acids including fish oil and flaxseed oil to balance out the abundance of omega-6 fatty acids in our diet.
Avoid or reduce vegetable oils, especially corn, canola, and soy oils, hydrogenated or partially hydrogenated fats (trans fats), and margarine.
Avoid low-fat foods and high-sugar carbohydrates.
And...enjoy the flavor of real, nutritious food!
References:
[1] http://www.westonaprice.org/making-it-practical/taking-the-fear-out-of-eating-fat?
[2] http://www.heart.org/HEARTORG/GettingHealthy/NutritionCenter/HealthyDietGoals/5-Goals-to-Healthy-Eating_UCM_307257_Article.jsp>
[3] http://www.cnpp.usda.gov/Publications/DietaryGuidelines/2010/PolicyDoc/Chapter3.pdf
[4] http://www.bmj.com/content/346/bmj.e8707
[5] http://dx.doi.org/10.1016/j.biopha.2006.07.080
[7] Br J Nutr. 2010 Dec;104(11):1586-600. doi: 10.1017/S0007114510004010.
[8] http://www.sciencedaily.com/releases/2005/08/050802123505.htm
[9] http://www.heart.org/HEARTORG/GettingHealthy/FatsAndOils/Fats101/Saturated-Fats_UCM_301110_Article.jsp>
[10] http://ajcn.nutrition.org/content/early/2010/01/13/ajcn.2009.27725.abstract
[11] http://www.naturalnews.com/035674_health_myths_saturated_fat.html#ixzz2tUyDlehf
[12] http://articles.mercola.com/sites/articles/archive/2002/08/21/saturated-fat2.aspx
[13] http://www.ncbi.nlm.nih.gov/pubmed/23674795
[14] http://www.westonaprice.org/know-your-fats/fatty-acid-analysis-of-grass-fed-and-grain-fed-beef-tallow