Coconut oil: the studies behind the headlines
Any time I review claims about a food or a supplement, I like to go to the original articles that have been quoted in the popular media. It is a time consuming process but very illuminating as it reveals how information can be quoted in such a way as to either deliberately or accidentally mislead the reader.
The research study that is the source of all the recent popular media articles on coconut oils is titled “Coconut oil consumption and cardiovascular risk factors in humans” by Eyres, Eyres, Chisholm & Brown. Published in Nutrition Reviews April 2016 issue, it was a review of 21 studies on the subject. Many of these had significant limitations to the study design, including the fact that while the effect of coconut oil consumption on cholesterol levels was studied, there was no evidence about disease outcomes. Many of the studies were very small (less than 50 people studied), only studied a specific population such as middle aged Indian men or Indonesian subjects for example, or were observational where correlations were made between health and coconut oil intake based on what people reported about their diets.
Evidence from studying populations who consume substantial amounts of coconut oil is often used as proof that coconut oil does not have negative effects on cardiovascular health. This needs to be looked at a bit more critically. Indigenous people who eat a lot of coconut do so by eating the unprocessed coconut flesh or drinking the milk straight from the coconut or occasionally squeezing the flesh to produce coconut cream.
The extraction and use of concentrated coconut oil by mass produced industrial methods is a relatively recent phenomenon. It is usually a highly processed commercial product which is refined, bleached and deodorized retaining none of the original coconut flavour or aroma. Virgin coconut oils are unrefined and still smell and taste like coconut.
Most coconut oil is consumed in indigenous populations in India, Sri Lanka, Phillipines, Polynesia and Melanesia ( yes I had to look these up in an Atlas too!) The Kitavans of Papua New Guinea have a low incidence of cardiovascular disease. Their diet consists of fish, tubers, fruit and whole coconut with fat calories comprising 20 per cent of their total calories. Importantly though, the average Body Mass Index of these islanders is 20. This equates to a weight of 58kg (128 pounds) for a person of 5’7” or 170 cm tall. That is really skinny by Western standards.
Another study compared Samoans living in Western Samoa with those living in the United States. The Samoans living in the U.S. eating the Standard American Diet had a increased risk of cardiovascular disease and metabolic syndrome (which usually leads to diabetes) compared to those eating the traditional diet of lots of coconut, some fish and fruits and tubers and minimal processed foods.
Yes, populations who eat a lot of coconut seem to be really healthy - but lets be real people! They are also very slim, active and eat a mostly plant based whole food diet with almost no processed food. So if you, like most Westerners, have a fridge packed full of meat and dairy products and oil-based salad dressings and cupboards groaning with bags of chips and boxes of crackers and cookies, adding a tablespoon (or glob) of coconut oil a day is likely not going to confer any health benefit.