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| There is a dearth of validated research to support the claims for virgin coconut oil -particularly about alleged benefits such as coronary artery disease (CAD) and stroke prevention, sustained weight loss, insulin regulation or a cure for Alzheimer's. Photo: 123rf |
The main MCTs in coconut oil are lauric acid, caprylic acid and decanoic acid – over 63% of normal coconut oil is made up of MCTs. These MCTs are also saturated fats – but they are processed rather differently from other saturated fats.
No MCT is known to be an essential fatty acid; they are not digested in the same way as other fats, and the body cannot store them easily as adipose (fat) tissue. They are processed more by the liver rather than via the normal digestive system and the calories from ingested MCTs are therefore normally expended rather faster and more immediately than for the other fats churning through the digestive system.
While the fact that MCTs cannot be quickly turned into fat tissue may be a benefit, the effect of loading the liver with excessive MCTs would appear to be an increase in liver fat (resulting in a higher propensity for diabetes), according to a Swedish study.
Also, the saturated fats in coconut oil have been shown to increase the low-density lipoprotein (LDL) count (hence increasing the cholesterol circulating through the body), though not as much as butter but rather more than unsaturated plant fats.
There is a dearth of validated research to support the claims for VCO – particularly about alleged benefits such as coronary artery disease (CAD) prevention, stroke prevention, sustained weight loss, insulin regulation or a cure for Alzheimer’s.
Most of what you can read are unverifiable anecdotal claims or results from small private studies with little statistical relevance.
Some side effects associated with consuming MCTs have also been reported, usually related to digestive problems and oddly, some minor cognitive issues.
The main noted benefit is that MCTs tend to have a high smoking point, making them particularly suitable for use as oils for frying – though the price of VCO would make this prohibitive.
Please note that industrial coconut oils used for commercial cooking generally tend to be partially hydrogenated (especially in tropical countries), rendering it rather detrimental for consumption – so if you must use coconut oil, then please do check on its suitability as hydrogenation turns the oil into unhealthy trans-fats.
What we can infer
In the absence of hard research about quantifiable health benefits, we can use some general demographics to infer the health properties or otherwise of coconut oil – and as one of the major health benefits claimed for coconut oil is
Coconut oil and coronary heart disease.
prevention of CAD, the statistic chosen is the global death rates due to CAD published by the WHO in 2014.
In 2011, the country credited with the highest consumption of dietary coconut oil per capita in the world is Sri Lanka, followed by Fiji, Guyana and Indonesia.
In the WHO table of CAD death statistics, out of 172 countries, Sri Lanka was ranked 31st worst in the world, Fiji at 19, Guyana at 14 and Indonesia came in at 97.
The relatively random distribution in the table of these countries suggests that MCTs are probably not a root cause of cardiovascular problems, even though three of the top coconut oil consuming countries (Sri Lanka, Fiji and Guyana) are in the top 19% of the number of CAD deaths.
It also suggests strongly that even if coconut oil has an effect on CAD, there are other (unknown) factors which are more compelling in determining CAD.
To put things in perspective, countries such as Turkmenistan, Ukraine, and Uzbekistan were ranked in the top 3 for CAD-related deaths – the death toll in Turkmenistan was a staggering 212% higher than Guyana for the number of deaths per 100,000 of population. These countries definitely do not include MCTs in their diets.
Curiously, the countries with the lowest CAD deaths are South Korea, France, Japan, Luxembourg and the Netherlands – and the diets in these countries are also almost exclusively devoid of coconut oil, and MCTs in general.
So, from the data, it would be inaccurate to assume any link between the low consumption of MCTs and general heart health as both the worst and best countries both consume very low levels of coconut oil MCTs.
Similarly, a high consumption of coconut oil does not demonstrate any obvious CAD benefits either.
All that can be said with any degree of certainty is that the high consumption of coconut oil does not immediately appear to have any direct statistical relevance on death rates due to heart disease – hence the staunch claims about the CAD benefits from ingesting coconut oil (and VCO) are somewhat questionable, or at least still open to detailed investigation.
The case of strokes
The same random distribution also applies if we look at the general death statistics for strokes – prevention of strokes is another alleged health benefit of consuming coconut oil.
In this statistic, Indonesia is the very worst country out of 172 countries studied, followed by Sri Lanka at 105th worst, Fiji at 96 and Guyana placed very high at 4th place.
However, as mentioned, this is a rather crude, simplistic analysis to see if there exists any immediately discernible health trends about strokes linked to the consumption of coconut oil – and it appears that there are none.
Or more accurately, if there are any coconut oil-related health benefits against strokes, then they are quite seriously outweighed by other unknown factors, especially in Indonesia and Guyana.
It should be noted that the countries with the lowest incidence of strokes are Switzerland, Canada, Israel, Qatar and France – with the notable country being France as whatever they are doing or eating, it certainly seems to maintain low death rates from CAD and strokes.
What about the Pukapukans and Tokelauans?
On the claimed promise of coconut oil promoting sustained weight loss, there are two atolls in Polynesia called Pukapuka and Tokelau – and studies on the populations on these islands have been used to disprove the suggestion that coconut oil cannot cause obesity (or that coconut oil can somehow “burn” off existing fat).
In summary, researchers determined that some 63% of the Tokelauan diet came from ingesting coconut products compared to 34% in the Pukapukan diet – and the simple (predictable) end result was that the Tokelauans were in general considerably heavier and fatter than the Pukapukans. Heart disease was quite rare for both populations though – but this may be due to other factors, such as their relatively quiet lifestyles with little stress.
To be fair, both sets of islanders were consuming coconut-derived foods, and not just the oil – and the significance of this is unclear at present.
What is rather clearer is that an April 2016 review of eight trials and 13 studies involving coconut oil came up with the somewhat soggy suggestion that replacing coconut oil with normal unsaturated fats “would alter blood lipid profiles in a manner consistent with a reduction in risk factors for cardiovascular disease”. Basically, the review concluded that on balance, normal unsaturated fats are better for heart health than coconut oil.
Good news for diabetics?
One sanguine use of coconut oil was reported in spring 2015 when it was announced by a Sri Lankan university that coconut oil can drastically reduce the calories available from rice, or at least push the Glycaemic Index (GI) of rice down to safer levels.
It has already been known for some time that fried rice or rice cooked in oils have rather reduced GI ratings compared to steamed or boiled rice – and the simple act of boiling rice in water containing 3% by weight of coconut oil (and then chilling it for hours) was claimed to reduce the rice calories significantly, around 10-15%.
There have been no new developments on this research since last year, though I do check up on it occasionally.
Mainly I am fascinated about how coconut oil can “wedge” its way into the glucose structures of rice and rearrange them into “very tight bonds” which are more resistant to digestion, as asserted.
In chemical terms, the big deal was that they have discovered a simple method to infiltrate the starches in rice (known as amylopectin and amylose) with coconut oil and turn them into less-digestible retrograde starches.
At least that is the theory, though it is not certain if the cooking techniques of various cultures may also have an influence. For example, some cooking conventions may require the chilling or overnight storage of cooked rice.
More pertinently, I would like to know if using other oils also has the same effect or whether this is a special property of coconut oil. Regardless, the news was big enough to be presented at the American Chemical Society’s national meeting in 2015.
If something sounds too good to be true
Sometime ago, at the urging of a friend, I bought an expensive jar of VCO, looked at it a few times, did some research and gave the jar away. This is not to say that VCO or coconut oil is bad for health in any way, provided it is consumed in moderation – it is just an example of my personal reaction to extravagant claims which don’t (currently) make any sense.
In summary, it is always reasonable and fair to confer the benefit of doubt when encountering something new – but in the absence of any further illuminating or supportive data, my general principle is that if something sounds too good to be true, then it is almost certainly a bad idea to believe in it.
http://www.star2.com/living/viewpoints/2016/08/14/the-coconut-oil-story-the-virgin-coconut-oil-story/
