Rediscovering the truth of the coconut: Coconut oil in a healthy diet

(First of two parts)

The coconut tree is one of the most iconic images of the Philippines, and indeed of much of the tropics. But although the coconut is called the “Tree of Life” wherever it grows, coconut oil has been attacked as an unhealthy oil for over 50 years and has suffered neglect. This two-part essay will discuss the recent history of coconut oil, and how it is being rediscovered as one of the world’s healthiest oils. 

The campaign against saturated fat

Many people in the tropics had been surviving — and thriving — on coconuts in their diet for many millennia. Not once was it ever reported that coconuts were unhealthy, until the 1950s when Dr. Ancel Keys, an American medical researcher, declared that coconut oil was harmful because it was a “saturated fat” that caused coronary heart disease.

Keys had a two-pronged attack: the first was against saturated fat and the second against cholesterol. He connected the two by claiming that saturated fat raised one’s cholesterol and that high cholesterol caused heart disease.

In 1987, Keys published a paper which presented data from seven countries — none of them coconut-consuming countries — to support his claim that saturated fat caused heart disease. His key evidence was a graph (shown in Figure 1) which showed a correlation between the amount of saturated fat consumed and heart disease.

Since coconut oil is a vegetable oil that is about 92 percent saturated fat, it was concluded that coconut oil must be harmful. Because of this proclamation, people began to shun coconut oil.

What are fats and oils?

Fats and oils are a group of chemical compounds with different numbers of carbon atoms, generally from eight to 18 atoms, linked in a linear arrangement called fatty acids. Fats and oils can be found in meat, fish, nuts, and seeds. Different fats and oils from animals and vegetables have characteristic profiles of fatty acids.

Animal fats are high in “long-chain saturated fats,” in particular palmitic acid and stearic acid, which are 16 and 18 carbon atoms long, respectively. Coconut oil is high in “medium-chain saturated fats,” in particular lauric acid, which is 12 carbon atoms long. (Lauric acid is also found in mother’s milk.)

“Saturated” and “unsaturated” fats refer to different variations in the carbon to carbon bonds. Saturated compounds are more chemically stable than unsaturated compounds.  Fatty acids which have several sites of unsaturation are “polyunsaturated.”

In the body, long-chain fats and medium-chain fats are metabolized differently. Long-chain fats form the bulk of lipoproteins, known by their more familiar acronyms LDL and HDL, which transport cholesterol around the body. 

In contrast, most of the medium-chain fats are transported directly to the liver and are metabolized quickly to generate energy for the body. Thus, medium-chain fats have different physiological effects from long-chain fats.

Coconut oil is unique among fats and oils in that it is over 65 percent medium-chain saturated fat. Other common vegetable oils, such as corn, olive, and soybean oil, are long-chain fats with a high proportion of unsaturated and polyunsaturated fats. Animal fat, on the other hand, has a high proportion of long-chain saturated fat.

Since Americans eat a lot of meat, they ingest a large amount of long-chain saturated fats. Unfortunately, American dieticians and medical doctors simply lumped all saturated fats into one group. Thus, coconut oil was dragged into the anti-saturated fat guideline.

The dietary guidelines for Americans

In 1980, the US Department of Agriculture introduced its “Dietary Guidelines for Americans” which advised Americans to have a low-fat diet and to replace saturated fat with unsaturated fats. This constituted another blow against coconut oil and its consumption in the US and the Philippines plummeted in favor of polyunsaturated oils and margarine which contained large amounts of trans-fats.

Trans-fats are harmful by-products from the process of hydrogenation of polyunsaturated oils. Ironically, polyunsaturated oils were hydrogenated to produce saturated fats, which Americans had proclaimed to be harmful. In the process, they produced trans-fats which were estimated to be the cause of 30,000 to 100,000 premature coronary deaths per year in the US.

Today, after 30 years and seven editions of the “Dietary Guidelines,” we can judge whether this advice worked. Today, we see an American population that is over 70 percent overweight, 30 percent obese, and number 1 among developed countries in incidence of obesity.

Recent health statistics show how wrong Ancel Keys and the official US dietary advice have been. European countries, which largely ignored American advice, showed that a high fat diet did not correlate with heart disease. In fact, the opposite is true: data from Oxford University showed that European countries that consumed more fat had lower incidence of heart disease (Figures 2 and 3).

Figures 2 and 3 show that high fat consumption correlates with lower incidence of death from coronary heart disease. (Figures 2 and 3 were taken from European cardiovascular disease statistics, 2008 edition, University of Oxford.)

What about cholesterol? Doesn’t high cholesterol put one in great danger of heart disease? In 2010, WHO published data on the incidence of cardiovascular disease (CVD) and total serum cholesterol collected from 192 countries (Figure 4). As the data show, there is absolutely no correlation between CVD and cholesterol. In fact, Colombia which has the highest level of cholesterol has an incidence of heart disease which is below the global average, while Turkmenistan which has the “recommended” cholesterol level of 200 mg/dL has the highest incidence of heart disease! Mexico, which has the highest per capita consumption of cholesterol-rich eggs, also shows below average incidence of CVD. 

Clearly, something must be wrong with the Ancel Keys hypothesis. Indeed, he has been accused of using only the data which supported his hypothesis. Meanwhile, Americans have become overweight and obese.

Evidence from the tropics

During the 1980s, several  research reports from the Philippines, India, Indonesia, and the Polynesian Islands — countries that actually consume coconuts in their diet — were published and these reports showed that coconut oil did not have a negative impact on heart disease and may, in fact, be beneficial.

For example, in 1981, Dr. Ian Prior, a researcher from New Zealand, showed that Polynesians who consumed high amounts of coconut in their diet had normal levels of cholesterol and low incidence of heart disease. In 1987, Dr. Rodolfo Florentino and Dr. Aida Aguinaldo, from the Food and Nutrition Research Institute of the Philippines, showed that Bicolanos, who had the highest consumption of coconut in the Philippines, had the lowest incidence of heart disease and cardiovascular disease among all regions surveyed.

Meanwhile, Pacific island countries, such as Nauru and Micronesia, which abandoned their coconut-based traditional diet in favor of the US diet of canned meats and other processed foods, soybean oil and margarine, have become the most obese in the world.

The health food boom

Given the failures of the US Dietary Guidelines and the anti-cholesterol campaign, coconut oil, in particular virgin coconut oil, has been rediscovered as the healthy oil that it is. Interest in coconut oil — indeed in all things coconut, such as coconut water and coco sugar — has been increasing globally. This is undoubtedly a good thing both for the coconut industry, as well as our own health, because history tells us that its health benefits are for real.

But this positive boom comes with a challenge: sooner or later, people will want to have scientific explanations for why coconut oil is good for one’s health. We must continue to support the research that will tell us why coconut oil should deserve the label as one of the world’s healthiest oils.

(To be continued)

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Dr. Fabian Dayrit is a professor of Chemistry at the Ateneo de Manila University and is a member of the National Academy of Science and Technology (NAST), Philippines. In August 2013, he co-authored the book, “Coconut Oil: From Diet to Therapy,” whose first edition was written by his father, Dr. Conrado Dayrit. E-mail at [email protected].