Saturated fats have been demonized for decades as "unhealthy" and a major contributor to heart disease. While some saturated fatty acids may have an overall negative effect on our health, it is important to understand that not all saturated fatty acids are created equal, and the inclusion of certain saturated fatty acids in your diet may actually be very beneficial for your health.
Saturated fats and the lipid hypothesis
In the early 1980s, the lipid hypothesis came to the forefront of public medicine. Based on research done by Ancel Keys, saturated fat and cholesterol were implicated as the leading cause of cardiovascular disease (CVD) . In 1992, the US government implemented changes to the food pyramid in an attempt to drastically curb the saturated fat intake of its citizens . Was this, in fact, a positive change? Subsequent investigations have shown that the researched conclusion may not be as accurate as assumed, stemming from the fact that all saturated fats are not created equal. I will attempt to break down saturated acids categorically, and based upon my recommendations in the summary, you can decide for yourself whether some saturated fatty acids may be lacking in your own diet and how they could possibly positively affect your health.
Classification of saturated fats
Saturated fats can be broken down into three categories: short, medium, and long chain fatty acids. The names refer to the length of the tail of the particular molecule.
Short chain fatty acids
The most common short chain fatty acids are butyric and caproic acids, which are found in grass-fed dairy products.
Short chain fatty acids aid in "gut health" by providing energy for colonic epithelial cells and promoting the growth of healthy colonic epithelium. An unhealthy digestive tract has been linked to depression, anxiety , and a lowered immune system response. Short chain fatty acids have also shown to have anti-inflammatory properties in patients with ulcerative colitis and inhibit the growth of colon cancer cells.
Medium chain fatty acids
There are three medium chain fatty acids: caprylic, capric and lauric acids which can be found in coconut oil and palm oil. When olive oil was replaced with MCT oil, subjects who consumed MCT oil lost more weight. MCT oil, which is known to induce a ketogenic state, has been studied as a treatment for Alzheimer's disease with promising results.
On a personal note, I add grass-fed butter and MCT oil to my morning coffee (as per the " bulletproof coffee" protocol) and have found it to be highly effective for increasing my overall productivity and cognition.
Long chain fatty acids
Certain long chain fatty acids can contribute to cardiovascular disease, while others have been shown to be neutral or benign. Unfortunately, many people are apt to consume too many of the unhealthy long chain saturated fatty acids on a daily basis. The long chain fatty acids are myristic acid, palmitic acid, and stearic acid.
Myristic acid and palmitic acid were compared in a study and shown to increase LDL cholesterol levels in test subjects . When LDL becomes oxidized it contributes to cardiovascular disease and metabolic syndrome. Myristic acid was found to have a more profound effect on cholesterol levels than palmitic acid. An interesting fact to keep in mind is that myristic acid is seldom naturally occurring, but is more commonly and abundantly found in processed foods.
As previously mentioned, palmitic acid in isolation, does raise LDL levels. However, it is to a lesser extent than myristic acid. Linoleic acid (unsaturated fatty acid) has been implicated in lowering LDL levels and is commonly found in the same foods that contain palmitic acid; palm and coconut oils being two examples . This signifies that the detrimental health effects of palmitic acid may be exaggerated, but significant in terms of overall diet.
Stearic acid was consequently determined to be detrimental to one's health. However, a subsequent study revealed that when studied in isolation, stearic acid actually contributed to a decrease in LDL levels leading to an improved overall cholesterol ratio.
But I thought all saturated fats caused heart disease
There is scientific evidence indicating that the consumption of saturated fats does not cause cardiovascular disease and that it has therefore been unfairly demonized . A scientific review was conducted to identify the effect of saturated fats on cardiovascular health. Four studies spanning across 35 countries assessed national fat consumption and mortality from coronary heart disease. In the majority of these studies, no positive correlation between saturated fat consumption and higher risk of atherosclerosis and cardiovascular disease was found . Furthermore, a meta-analysis of prospective epidemiological studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of coronary heart disease . The unfortunate truth for people who eliminated fat from their diet because of worries about heart disease is that low-fat diets have been shown to make no difference on CVD outcomes in multiple studies.
I hope it is now evident that not all saturated fatty acids are created equal and that while some contribute to heart disease; others can be very beneficial with specific benefits. You should avoid saturated fats that are processed or otherwise not readily available in a natural form, including pressed seed oils (i.e., canola and soybean oil), bleached or hydrogenated fats (like margarine) and any fats that come from a "non-living" source (i.e., manufactured fats such as trans-fats). The best sources of saturated fats are coconut oil, avocado, grass-fed beef, pastured butter, tallow, ghee, and free-range eggs. These foods contain fats that are beneficial to our health as well as containing the various fats in ratios that are conducive to achieving optimal health. My hope is that you use the information presented in this article to make better decisions about which saturated fats should be included and excluded from your diet.
In the end of this article I would like to state that the article was taken from several different sources of media, including the following books:
1. Wong, Julia M.; de Souza, Russell; Kendall, Cyril W.; Emam, Azadeh; Jenkins, David J. (2006). "Colonic Health: Fermentation and Short Chain Fatty Acids". Journal of Clinical Gastroenterology 40 (3): 235-243.
2. Vanhoutvin, SA; Troost, FJ; Hamer, HM; Lindsey, PJ; Koek, GH; Jonkers, DM; Kodde, A; Venema, K et al. (2009). "Butyrate-Induced Transcriptional Changes in Human Colonic Mucosa". In Bereswill, Stefan. PLoS ONE 4 (8): e6759.
3. Flight V. Evidence does not support saturated fats being harmful for cardiovascular health. J Prim Health Care. 2012 Jun 1;4(2):174.
4. Petousis-Harris H. J Prim Health Care. 2011 Dec 1; 3(4):317-9. Epub 2011 Dec 1.
5. Ravnskov U. The questionable role of saturated and polyunsaturated fatty acids in cardiovascular disease. J Clin Epidemiol. 1998 Jun;51(6):443-60.
6. Patty W Siri-Tarino, Qi Sun, Frank B Hu, and Ronald M Krauss. Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. Am J Clin Nutr. 2010 March; 91(3): 535-546.
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