Walking through the grocery aisles, one thing has become clear: coconut oil has come to officially dominate the store. Since when did everyone swap out the usual oil suspects and go nuts for coconuts?
This is not to say there is anything inherently “wrong” with choosing to consume coconut oil. Coconut oil is tasty and can be part of a healthy diet when consumed in moderation. The problem with coconut oil is that it is being touted as this magical, cure-all substance that can do anything from soothing unrelenting frizzy hair to curing chronic diseases. Further, a survey found that there is a discrepancy in the perception of coconut oil as a “health food” between the American public and those involved in nutrition. The American Heart Association recently published a scientific advisory report that recommended against consuming coconut oil [1]. This was met with scrutiny from various media outlets and healthy living figures on social media. So, let’s take a closer look at the current science behind coconut oil and heart health.
Coconut oil has been a staple food among indigenous populations in India, Sri Lanka, the Philippines, Polynesia, and Melanesia and has more recently made its way into the Western diet [2]. Observational studies of indigenous populations that consume significant amounts of coconut oil have found no adverse effect in regards to cardiovascular disease (CVD) risk [2]. However, these types of studies cannot prove causality and are subject to various biases, including recall bias. Further, these populations were more likely consuming a traditional diet with sufficient polyunsaturated fats, limited refined carbohydrates, and fiber-containing coconut products, such as coconut flesh and flour, which research has found does not increase risk for heart disease [2].
Coconut oil had previously been viewed as an “unhealthy” fat due to its high saturated fatty acid (SFA) content [3]. Upon closer examination, researchers found these saturated fats were primarily comprised of medium-chain saturated fatty acids (MCFAs). Compared to long-chain saturated fatty acids (LCFAs), MCFAs are smaller in molecular size, which increases their solubility in water [3]. Unlike LCFAs, which follow the lymphatic system for absorption, MCFAs are absorbed faster in the intestine into the portal venous system and are carried to the liver to be oxidized for energy [3]. This direct process reduces the amount of free MCFAs in the blood circulation and has been speculated to be a potential cardioprotective mechanism of coconut oil [3].
A recent systematic review has found that coconut oil raises total cholesterol, HDL, and LDL, when compared to cis unsaturated plant oils, whereas butter raises total cholesterol, HDL, and LDL the greatest amount [2]. This suggests that coconut oil may fare better than butter for desirable lipoprotein levels, but ultimately it may be best to choose cis unsaturated plant fats to help reduce risk for CVD [2]. This finding was what encouraged the American Heart Association to caution against consuming too much coconut oil, since the 7 studies included in the review all reported increases in LDL cholesterol, with significance reported in 6 of these studies [1]. However, the current literature for the effects of coconut oil on heart health is relatively sparse and the evidence of an association between consuming coconuts and risk factors for heart disease is mainly of poor quality [2]. Coconut oil has recently become trendy among the health food community, so, while it is probably best to not consume coconut oil excessively, a little bit here and there will likely be fine.
References:
- Sacks, F.M., et al., Dietary Fats and Cardiovascular Disease: A Presidential Advisory From the American Heart Association. Circulation, 2017. 136(3): p. e1-e23.
- Eyres, L., et al., Coconut oil consumption and cardiovascular risk factors in humans. Nutr Rev, 2016. 74(4): p. 267-80.
- Babu, A.S., et al., Virgin coconut oil and its potential cardioprotective effects. Postgrad Med, 2014. 126(7): p. 76-83.
