Lipid Luminations: Coconut Oil Supplementation and Lipids

Coconut oil consumption is rapidly increasing. This increase is in part because of supposed health benefits, including relieving mental fatigue and depression, altering risk factors of cardiovascular disease, and modifying cognition.1 Despite limited evidence for these purported benefits, consumption and therefore demand in the food industry is rising.2

To better delineate the potential for coconut oil to modify cardiovascular disease (CVD) risk factors, including serum cholesterol, it is important to understand coconut oil composition. Coconut oil is extracted from the meat of the coconut. It primarily is composed of saturated fat (92 percent) and, therefore, is solid at room temperature. Because of its high saturated fat content, coconut oil has a long shelf life. This makes coconut oil attractive in food processing and the baking industry.

While it is tempting to classify fats by saturation status (e.g. saturated fat, monounsaturated fat), fatty acid chain length also is important. Saturated fatty acids in coconut oil is mostly lauric acid (12:0) at 45 to 56 percent, myristic acid (14:0) at 16 to 21 percent, and palmitic acid (16:0) at 7.5 to 10.2 percent.3 Because the saturated fat in coconut oil is largely composed of the medium-chain triglyceride (MCT) 12:0, this differentiates coconut oil from other saturated fat food sources, such as lard and beef tallow. These MCTs, which are made up of fatty acids that are six, eight, 10, or 12 carbons in length (6:0, 8:0, 10:0, and 12:0, respectively), are transported directly from the intestinal tract through the portal vein to the liver and primarily are used as an immediate source of energy. This is considered beneficial as a higher rate of fatty acid oxidation in the liver is thought to reduce the accumulation of lipid in adipocytes.

When delineating the impact of coconut oil consumption on cardiovascular health, one also must consider how coconut oil is extracted and processed. Coconut oil can be largely unprocessed (virgin coconut oil) or processed (refined coconut oil). The Asian and Pacific Coconut Community (APCC) sets standards for virgin coconut oil (VCO). VCO must come from fresh, mature coconuts, and must not have undergone chemical refining, bleaching, or deodorizing. On the contrary, conventional or refined coconut oil widely used in the food and supplement industry is made from dried coconut — otherwise known as “copra” — that is cooked, bleached, and has had chemicals added.4 It is possible that the polyphenol/antioxidant content in virgin coconut oil may provide health benefits not seen in refined coconut oil; 4 the specific type of coconut oil used in trials must be considered when determining the impact of coconut oil on cardiovascular health.

Evidence that coconut oil is beneficial in treating or preventing CVD is limited. In 2014, the Academy of Nutrition and Dietetics position paper on dietary fatty acids concluded that coconut oil is not currently recommended for consumption and that additional peer-reviewed literature is needed before any statements about its health benefits are made.5 In a recent comprehensive review of 15 randomized controlled trials (RCTs) in humans, the authors concluded that coconut oil consumption increased total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C), and that removing coconut oil from the diet reduced total cholesterol and LDL-C with variable effects on HDL-C.6  The specific type of coconut oil used in these trials is not known.

As coconut oil is primarily saturated fat, research delineating the impact of saturated fat on risk factors for CVD is relevant. A recent Cochrane Review of 15 RCTs of 59,000 participants reported that decreased saturated fatty acid intake led to a 17-percent reduction in CVD risk.7

The 2015 Dietary Guideline Advisory Committee reported saturated fat as a “nutrient of concern” in the U.S. and recommends an intake of less than 10 percent of total daily calories.8 The NLA Recommendations for Patient-Centered Management of Dyslipidemia: Part 2 supports a cardioprotective eating pattern “that includes <7% energy from saturated fat, with minimal intake of trans fatty acids to lower atherogenic cholesterol (LDL-C and non-HDL-C).” Strength A, Moderate Quality Evidence. Unsaturated fats can be used to partially replace saturated fats and proteins, as long as the goal of getting <7 percent of energy from saturated fat is met.9

It is important to note that some extrapolate the health benefits of MCTs to coconut oil itself. However, most studies that have reported the impact of MCTs on health outcomes have used or reported on the benefits of 8:0 and 10:0.10  Therefore, the results of these studies cannot be extrapolated to consumption of coconut oil itself, because a majority of its MCTs are 12:0.5

With a majority of the population over-consuming saturated fats and the evidence linking saturated fats and heart disease, it is prudent to consider avoiding the addition of food products, including coconut oil, that add saturated fat to the diet. Additional research is needed to identify whether particular fatty acids or other components in coconut oil may provide beneficial effects on serum cholesterol levels and cardiovascular health.

Disclosure statement: Julie Bolick has no disclosures to report. Dr. Rasmussen has received salary as a co- investigator for a clinical trial from Nutrabiotix LLC.

References are listed on page 36 of the PDF.