Beneficial Dietary Oils: Fats are Not Always Bad for You

Much has been published about the health costs associated with being overweight or obese. There are reams of clinical and scientific data demonstrating the direct correlations of excess fat with hypertension, atherosclerosis, stroke, and type 2 diabetes, to name just the most detrimental disorders. These conditions are indeed deadly and millions of Americans suffer from the ultimate fate due to poor dietary choices and sedentary lifestyles.

It is absolutely critical that individuals understand that it is not just excess carbohydrate, but also excess fat, and/or excess protein intake in ones diet that will ALL result in the accumulation of fat and thus, body mass (weight). But as the diet and food industry likes to point out, not all types of carbohydrate or fat are equal contributors to the obesity epidemic. Most people have become aware of the dangers of "trans" fats and "saturated" fats in the diet. Indeed, in the US and most European countries the use of trans fats in manufactured food products is banned due to the direct correlations between their consumption and diseases such as diabetes and cancer.

However, a fat is not just a fat and many naturally occurring dietary fats are extremely beneficial to the pursuit of a healthy lifestyle. The most significant class of healthy fats are the polyunsaturated fatty acids (PUFAs), in particular the omega-3 PUFAs that are abundant in cold water fishes such as tuna. However, even certain saturated fats have distinct health benefits. I will briefly review the health benefits of several different types of fats in this post but for more details on the sources and benefits of many of these types of fats go to the following pages of my website:

Fish and Krill oil: The consumption of fish has long been known to be of significant health benefit, particularly deep cold water fishes. The presence of omega-3 PUFAs in fish oils is the principal reason for the benefits of their consumption. Krill (tiny shrimp like crustaceans) are also rich in omega-3 PUFAs. The beneficial fatty acids in both of these food sources are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). EPA is a 20-carbon PUFA (5 carbon-carbon double bonds: sites of unsaturation) and DHA is a 22-carbon PUFA (6 sites of unsaturation). Both of these fatty acids are found in complex lipid molecules called triglycerides (3 fatty acids attached to to the 3-carbon alcohol, glycerol) and phospholipids. Phospholipids are similar to triglycerides in that they are composed of a glycerol backbone but they also have phosphate attached to one of the carbons of glycerol instead of 3 fatty acids. Fish oils contain EPA and DHA in triglycerides, krill oils contain these fats in phospholipids. These different complex lipids contribute significantly to the differences in bioavailability of EPA and DHA from fish versus krill oils. Krill oil phospholipids provide a much higher level of uptake and tissue re-distribution of both EPA and DHA (but especially DHA) compared to that of fish oil triglycerides. For this reason, although both are healthy sources of EPA and DHA, the consumption of krill oil supplements is "more bang for the buck". The benefits of both EPA and DHA are broad and include restriction in the extent of inflammation; promoting cardioprotection (reduce the likelihood for atherosclerosis and stroke); enhancement of fatty acid metabolism in the liver resulting in reduced levels of lipoprotein production, specifically very low density lipoproteins, (VLDL) which thus, reduces the level of circulating low density lipoproteins (LDL) the so-called "bad cholesterol". EPA and particularly DHA have significant roles in early brain development and have been implicated in the ability to alter mood and behavior.  

Olive oil: Olive oil is one of the major constituents of the healthy "Mediterranean diet". The primary beneficial fatty acid found in olive oil is oleic acid. Oleic acid is an 18-carbon monounsaturated fatty acid (MUFA). Oleic acid is an omega-9 MUFA that, along with palmitoleic acid (16-carbon MUFA) constitutes the most biologically relevant MUFAs in humans. The oleic acid in olive oil is found in triglycerides and in fact free oleic acid is restricted from food grade olive oil due to its contribution to the rancidification (oxidation of edible oils) of olive oil. However, when consumed in the triglyceride form the oleic acid is released in the small intestines by digestive enzymes and then it is absorbed. In intestinal cells oleic acid is converted to the fatty acid amide called oleoylethanolamide, OEA.

OEA is a potent bioactive lipid that exerts numerous positive effects in the body. Within the brain OEA stimulates the sensation of satiety (feeling full and no longer hungry) so it is a natural appetite suppressant. This effect of OEA constitutes a significant benefit to the addition of olive oil to the diet of anyone but particularly those who are overweight or obese. In the pancreas OEA stimulates the ability of glucose to induce insulin release. This effect of OEA constitutes an enormous benefit to olive oil in the diabetic diet. Because of these significant benefits of olive oil the food industry has ramped up the production of olive oil but buyer BEWARE!!! Many so-called olive oil products on the store shelves are NOT 100% pure olive oil but have been purposefully "contaminated" with cheaper and more abundant oils such as canola oil. Please do your due diligence and research the brands that are consistently 100% pure olive oil before buying. Even some brands that, as recently as 2-3 years ago, were 100% pure, are now known to be adulterated with other oils.

Try this experiment at home: when you wake up write down your perceived level of hunger, then consume 1 tablespoon of pure olive oil, wait 30 minutes and then ask yourself once again what is your perceived level of hunger!!!

Argan oil: Argan oil is produced by compression of the kernels of the argan tree (Argania spinosa). Most uses for argan oil with which people are familiar is its inclusion in cosmetics and hair care products. However, there are serious health benefits to the consumption of food-grade argan oil even though, as yet, it is not the easiest dietary oil to find in the grocery store. Argan oil is enriched in the MUFA, oleic acid. Indeed, as much as 50% of the fatty acid in argan oil is oleic acid. The health benefits of oleic acid are those outlined above for olive oil. Argan oil also contains numerous other beneficial lipids and polyphenolic compounds (plant-derived anti-oxidants). These additional beneficial lipid compounds include vitamin E (tocopherols) and carotenoids (think beta-carotene and carrots). Although there are numerous phenolic compounds in argan oil three compounds, tyrosol, catechin, and epicatechin have been suggested to exert anti-aging effects.

Coconut oil: Once denounced as being a bad choice for ones diet due to the presence of saturated fatty acids it is now clear that the fatty acids in coconut oil are quite beneficial. The two major fatty acids in coconut oil are octanoic acid (also known as caprylic acid) and lauric acid. Octanoic acid is an 8-carbon saturated fatty acid and it is a minor constituent of both coconut oils and palm kernel oils. Lauric acid is a 12-carbon saturated fatty acid that constitutes roughly 50% of the fatty acid in coconut oil. Both of these fatty acids are found in triglycerides in the oil. Both lauric and octanoic acids have demonstrated health benefits, but the benefits of total coconut oil has been clearly shown to be superior when compared to the individual fatty acids themselves. The consumption of what is referred to as extra virgin coconut oil has been shown to reduce numerous parameters of a diseased cardiovascular system (hypertension, high serum triglycerides, atherosclerosis, stroke); coconut oil reduces oxidative stress which is a major component of cellular aging; coconut oil increases the level of high density lipoproteins (HDL, so-called "good cholesterol") in the blood; and coconut oil also reduces inflammation. Coconut oil has also been shown to have antibacterial and anticancer effects.

Palm kernel oil (NOT palm oil): The benefits of palm kernel oil mimic those of extra virgin coconut oil due to the high concentration of lauric acid (as well as octanoic acid) in these oils. Palm kernel oil should NOT be confused with palm oil because the two are distinctly different in the composition of fatty acids. Palm oil is produced through compression of the palm fruit, whereas palm kernel oil is produced through compression of the palm seed. However, there are health benefits to both types of oil it is just that palm oil is low in lauric acid compared to palm kernel oil. One of the major benefits of palm oil is the high amount of antioxidant compounds of the carotenoid family (think beta-carotene and carrots). Indeed, the presence of the carotenoids imparts a reddish golden color to palm oil.


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