(Second of two parts)
Although coconut oil is known mainly as a dietary vegetable oil, it has found numerous other beneficial uses. This article will briefly describe three diverse applications which illustrate the usefulness of coconut oil, including their scientific basis. These applications include: antimicrobial, anti-obesity, and anti-cancer activities.
Coconut oil: Nature’s antimicrobial agent
In 1925, this small news item from the US Army and Navy General Hospital was published in Science journal: “Extensive experiments showed that common soaps were effective germicides in at least three types of infection, while soap made with coconut oil was markedly destructive to the organisms of typhoid fever.â€
This seemingly minor observation has grown into a major discovery regarding the antimicrobial properties of coconut oil. Extensive research in the 1970s by Prof. Jon Kabara at Michigan State University showed that lauric acid, which accounts for about half of the fatty acids in coconut oil, is the most potent among all fatty acids against gram-positive bacteria. A natural derivative of lauric acid, known as monolaurin, showed even more promising antibacterial activity.
However, what make lauric acid and monolaurin stand out against the usual antibiotics are its inherent safety (that is, very low toxicity in humans) and absence of microbial resistance which is common with antibiotics. Contrast this with antibiotics which have many undesirable side effects and which have been losing their efficacy due to the development of microbial resistance.
Coconut oil has been used to treat skin infection (including Candida albicans) and stomach ulcers (Heliobacter pylori), among others. Monolaurin has found use in cosmetics and pharmaceuticals and is now commonly used as a antimicrobial agent cum emulsifier in foods. In 2012, the World Dental Organization acknowledged that coconut oil is able to control bacteria that are responsible for tooth decay and recommended that coconut oil be regarded as a natural antibiotic which can be added as a main ingredient to oral healthcare products.
The scientific basis for the antimicrobial activity of lauric acid and monolaurin is attributed to at least two mechanisms. First, these two compounds have been shown to be most effective in disrupting the bacterial cell wall, in particular of gram-positive bacteria. This is consistent with the strongest surfactant effect of lauric acid. Second, lauric acid and monolaurin are able to interfere with the bacteria’s cell signalling process; this is believed to be the reason behind their ability to avoid bacterial resistance.
Coconut oil vs obesity
During the 1970s, nutrition researchers became interested in the metabolic response of humans to different types of fats. As a result of these studies, it was discovered that medium-chain fatty acids have the property of raising body temperature, a response called diet-induced thermogenesis.
In studies on humans which involved overfeeding human volunteers with both medium-chain fats and long-chain fats, it was shown that the former stimulated thermogenesis to a greater degree than the latter. Since coconut oil is unique in its composition of having over 65 percent medium-chain fats, even excess consumption will not make one fat compared with other fats and oils.
In 2003, Marie-Pierre St. Onge and co-workers from Montreal compared the effects of diets rich in medium-chain fats versus long-chain fats on body composition, energy expenditure, and fat oxidation among 24 overweight but healthy men. They found that the diet rich in medium-chain fats led to greater loss of adipose fat compared to long-chain fats and they recommended the use of medium-chain fats for the prevention of obesity.
In 2009, Monica Assunçao and co-workers in Brazil studied the effects of dietary supplementation with coconut oil versus soybean oil on the lipid profiles of obese women. They found that coconut oil raised the HDL level, improved the LDL/HDL ratio, and reduced the body-mass index (BMI) of the subjects. In contrast, soybean oil raised total cholesterol and LDL and gave an unfavorable LDL/HDL ratio. They concluded that coconut oil promotes reduction in abdominal obesity and does not cause dyslipidemia (abnormal amount of fat in the blood), in contrast to soybean oil which gave poorer results.
The scientific basis for the action of coconut oil in combating obesity has been attributed to increased metabolic rate and thermogenesis. Upon ingestion, medium-chain fats are brought directly to the liver where they are metabolized for energy unlike the long-chain fats which circulate in the blood stream before being brought to the liver.
Coconut oil vs cancer
In the 1980s and 90s, Dr. Clara Lim-Sylianco from UP Diliman carried out a number of studies using laboratory animals on the anticancer properties of coconut oil. She showed that coconut oil had two anti-cancer properties: first, it protected the test animals against carcinogenic substances; and second, it is able to protect germ cells of laboratory rats from carcinogenic substances. In addition, only coconut oil was able to cause a return of fertility of the rat even with a single dose.
Further, Dr. Sylianco was also able to show that coconut oil was superior to soybean oil in its anti-cancer action. What is the explanation for the efficacy of coconut oil over soybean oil? Soybean oil has polyunsaturated fats which readily form oxidation products which are toxic to the cell and attack the cell’s genetic machinery. Continuous ingestion of such oxidized compounds has been shown to increase tumour frequency and incidence of atherosclerosis in test animals.
Another important anti-cancer property of coconut oil is due to the ability of normal cells to utilize medium-chain fats for energy while cancer cells are unable to do so. Thus, by switching one’s diet from a sugar and carbohydrates to coconut oil, one can starve cancer cells for energy while providing healthy cells the energy that it needs. This enhances the survival of normal cells over cancer cells.
This may be the mechanism behind the effectiveness of virgin coconut oil in the case of Julie F. Julie developed cancer in the US and returned to her home province of Quezon with the cancer in her skull with no more medications and only her prayers. After reading about coconut oil, she began to prepare her own VCO and then consumed as much as she could of the oil, mixing it with her food and beverages. After six months she felt well and strong, with no signs or symptoms of her cancer. Upon returning to the US for medical follow up, she was told that her cancer was in remission! Asked what she was taking, she replied: “Nothing but virgin coconut oil!â€
Turning experiments, case studies and anecdotes into science
There are just three examples of the numerous documented claims that have been made for coconut oil. Other important diseases include inflammatory conditions, Alzheimer’s disease and epilepsy. Certainly there are many more questions that need to be answered and more research is needed to understand exactly how coconut oil works in each case. Coconut oil is nature’s gift that we are starting to unwrap only now.
Numerous laboratory animal studies and small clinical trials have already shown positive results. However, further research undertakings, including large clinical trials, have not been conducted because of their high cost. Coconut oil is like an orphan drug — promising cures with low financial return — which pharmaceutical companies have no interest in developing.
Coconut oil still has a lot of unrealized potential. Who will support its development?
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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 wrote the book “Coconut Oil: From Diet to Therapy.†E-mail at fdayrit@ateneo.edu.