Coconut oil is currently enjoying its 15 minutes of fame as the popular natural cure of the day. As is typical, this is based entirely on marketing, and not on science. As a result the public is largely misinformed about the net health effects of consuming coconut oil.

The American Heart Association recently put out a presidential advisory in which they discuss all aspects of fat consumption and heart risk. While it is only one small part of the advisory, the section on coconut oil is getting the most attention because of the disconnect between the science and public opinion. In fact they report that 72% of the public, when surveyed, expressed the belief that coconut oil was a “healthy food.” This compared to 37% of nutritionists (which, unfortunately, means that a third of nutritionists don’t seem to know what they are talking about).

This disconnect is clearly due to the marketing of coconut oil as a natural health food. There is a deeper cause, however, rooted in differences in interpreting the scientific literature. Health gurus (which I will distinguish from science-based nutritionists) tend to interpret the literature is a very superficial way. They take basic science studies and then extrapolate the findings simplistically to clinical effects. We have a vast scientific experience, however, that clearly indicates this is not a valid approach. Such simplistic extrapolations are almost certainly going to be wrong. Science-based professionals take a different approach – they systematically review at the evidence and think carefully about what it actually shows, what we can and cannot conclude. They give special weight to clinical studies that directly compare interventions and specific clinical outcomes.

There is also a cynical aspect to the marketing of “natural” cures and products. There is a lot of money to be made from marketing snake oil, which is a marketer’s dream. You can make up compelling health claims based on flimsy evidence and implausible or simplistic chains of reasoning, and then market cheap products with hefty price tags. Sometimes this is done explicitly, meaning that first a snake oil peddler will secure a supply of some exotic berry or nut, or even some waste or low quality food product – something they can buy cheap and in bulk, with little market value. They then manufacture bogus health claims for their product and promote them through health gurus and a willing media happy for the click-bait headlines that result.

Often the bad science and the cynical marketing work synergistically.

Meanwhile the actual scientific research may take years to catch up. It takes time to do the kinds of studies that will actually answer the question of health effects. But by then the public has already been marketed into true believers. Antioxidant hype is still going strong, despite the fact that the scientific evidence has failed to show any health benefit for antioxidant products. If enthusiasm for a product wanes because evidence shows it is worthless, that’s OK too. Snake oil peddlers can just move on to the next scam.

Coconut oil and health

The claims made for coconut oil, not surprisingly, essentially portray it as a cure-all. The first hit I get when I Google “Coconut Oil” is from the Wellness Mama, who claims that coconut oil is a:

Great Source of Healthy Fats– Over 50% of the fat in coconut oil is lauric acid. In fact, coconut oil is the richest source of lauric acid after breastmilk.

This is the opposite of the truth. She also claims that coconut oil is good for digestion, supports the immune system and hormones, and boosts mental function. Other gullible sites repeat these same claims. Let’s address the “healthy fats” claim first.

This claim is based on the fact that lauric acid will increase HDL (high density lipoprotein) levels in the blood. HDL is considered “healthy” cholesterol as it does not increase the risk of cardiovascular disease (CVD). However, the most recent data shows (summarized in the AHA report) that increasing HDL alone has little health benefit. Rather, we should focus more on LDL (low density lipoprotein) which carries significant risk for CVD. Lauric acid is a saturated fat, and saturated fats increase LDL. Lauric acid specifically increases both HDL and LDL, but this has a net negative health effect – it increases the risk of CVD.

A quick biochemistry aside for those who are interested: Triglycerides have a backbone of glycerol and three fatty acid “tails.” Fatty acids contain a carboxylic acid end and a long hydrocarbon chain, which is a chain of carbon atoms with hydrogen filling all the open bonds. A saturated fatty acid is saturated with hydrogen, meaning that all the carbon bonds in the hydrocarbon chain are single bonds, and there is the maximal amount of hydrogen. Unsaturated fatty acids have one or more double bonds between carbon atoms in the chain, and therefore less hydrogen. Monounsaturated means one double bond, and polyunsaturated means more than one double bond.

In general saturated fats increase LDL and contribute to CVD, while mono and polyunsaturated fats do not.

Back to coconut oil – coconut oil is 82% saturated fat, and is therefore one of the worst possible oils you can consume. Palm oil is also 82% and is therefore also an unhealthy oil to consume. By comparison butter is 63%, pork lard is 39%, and beef fat is 50%. That’s right – coconut oil is worse than lard. On the other hand, olive oil is only 14% saturated fat, and safflower oil is the lowest at 6%.

The AHA did not stop there; they reviewed seven clinical trials that looked directly at the effects on lipid profiles of consuming coconut oil. Of the seven trials all seven showed an increase in LDL, six of them to statistical significance. Further, the increase in LDL was comparable to consuming other saturated fats, such as animal fat. That conclude that because of this, and the fact that there are no proven benefits to consuming coconut oil, they recommend people avoid coconut oil as unhealthy.

This is the opposite recommendation as that from the health gurus, because they do not understand the scientific literature and draw the wrong conclusions from partial information.

What about the anti-microbial effects of coconut oil? This is also a common health guru claim because lots of things will kill bacteria in a petri dish. That does not mean it has clinically beneficial effects. I already discussed the practice of “oil pulling”, which is swishing and rinsing the mouth with coconut oil. There is no proven benefit for this practice, although it does seem to reduce bacteria in the mouth, but no more than rinsing with standard mouth wash.

The Health Mama and other gurus claim that eating coconut oil will have an antibiotic effect. This is possible but unproven. Coconut oil may disrupt the lipid coating on some bacteria. But why would you think this is beneficial? If true, then the primary effect would be to reduce normal GI flora. This would likely be a bad thing.

It’s interesting that the health gurus generally rail against the evils of overusing antibiotics, but then recommend a “natural” antibiotic for regular use and claim that it will magically be beneficial. They can easily flip their logic when convenient.

Like all products that claim to boost the immune system, or increase antioxidant effect, or kill bacteria – either they don’t work or you don’t want them to. If they actually have the claimed effect, it is probably bad for your health. You don’t want to mess with the normal homeostasis of your immune system, nor do you want to indiscriminately kill off your normal bacterial flora. Again this reveals the difference between sloppy and simplistic thinking on the part of gurus and careful, systematic, logical and evidence-based thinking on the part of scientists.

Coconut oil is not a health food

The bottom line is that coconut oil is not a health food. It is very high in saturated fat and you should avoid consuming it in any significant quantities. If you want to use it for its cooking properties or because you like the taste, that’s fine, just consume it in moderation (like all sweet and fatty treats). But do not be confused by the misleading marketing – coconut oil is not good for your health.

The other health claims made for coconut oil are all unsupported by scientific studies and make little scientific sense. With such claims, many people err on the side of being hopeful. This is not a rational position, however. We have a century of scientific experience to tell us that when it comes to preliminary or speculative health claims, do not be hopeful, be realistic. Casino owners want their customers to be hopeful rather than realistic too. It’s good for business, but it’s not good for your health. The vast majority of such claims will not turn out to be true, and you are far more likely to harm yourself than to help yourself by basing health decisions on such evidence.

Posted by Steven Novella

Founder and currently Executive Editor of Science-Based Medicine Steven Novella, MD is an academic clinical neurologist at the Yale University School of Medicine. He is also the president and co-founder of the New England Skeptical Society, the host and producer of the popular weekly science podcast, The Skeptics’ Guide to the Universe, and the author of the NeuroLogicaBlog, a daily blog that covers news and issues in neuroscience, but also general science, scientific skepticism, philosophy of science, critical thinking, and the intersection of science with the media and society. Dr. Novella also contributes every Sunday to The Rogues Gallery, the official blog of the SGU.