[Sciences/Junk Sciences] How the recent AHA recommendation on coconut oil is making many getting nuts (and why coconut oil is not an healthy choice)!

Coconut oil. Coconut oil. Yep, that same coconut oil that (almost) nobody knew about a couple of years ago and suddenly became the next big thing in fad diets. Some claimed it is healthier than vegetable oil (http://pilatesnutritionist.com/why-coconut-oil-is-better-than-vegetable-oil/; which turned out is not true), other claimed it can help you loose weight (https://authoritynutrition.com/coconut-oil-and-weight-loss/; that is also hard to imagine how to loose fat by keeping an high-fat diet) or even use it as a natural sunscreen (http://thecoconutmama.com/coconut-oil-sunscreen/; which of course will more likely help you roast like a rotisserie chicken).
You see the fad went a bit crazy with the habitual “wellness” bloggers making miraculous claim. The fact is coconut oil is no better than any oil and indeed maybe as bad as any saturated fats.
The only thing that I would say coconut oil is good, is giving you some tasty and crunchy fries that are not too greasy. Any French household know the “Vegetaline” brand (basically solid coconut oil that you mix with half sunflower oil to get a frying oil).

What is (in terms of chemical composition) coconut oil?

Coconut oil is extracted from the inner side of the coconut. It is also called copra oil. Some coconut oil are referred as “organic coconut oil” and even some referring as GMO-free coconut oil (you know the GMO-free project sticker that have no sense except operating as a form of racketeering? There are been never any GM-coconuts that hit the market. http://www.zebraorganics.com/organic-virgin-raw-coconut-oil-1-gallon-tub-zebra-organics.html?gclid=Cj0KEQjwyZjKBRDu–WG9ayT_ZEBEiQApZBFuK3KbEfSPhyNyx9z9eNUIwAmd6OwcxTWJUYKADA_fhEaAnvd8P8HAQ). Therefore, we consider all coconut oil equals (maybe slight variations between cultivars but this should not affect much the overall composition to be considered significant).

Before we discuss about the composition of coconut oil, it is important to know what a fatty acid is. Fatty acids (FA) are hydrocarbon chains (made of carbons and hydrogens) that are very similar to molecules belonging to alkanes (these are the molecules such as propane, butane and octane that are present in your propane gas tank right now fueling your grill, fueling your gas stove or fueling your SUV).
In contrast to alkanes, FA have a carboxyl (-COOH) “head” denominated and seen below:

We have two type of FA: saturated FAs (fully loaded with hydrogens) and unsaturated FAs (that have one or several C=C double bounds). Saturated FAs are usually found in fat products from animal origin (lard, butter, ghee…) whereas unsaturated FAs are usually found in plants (olive, rapseed/canola, corn, sunflower…) and in fish and seafood (usually polyunsaturated fatty acids or PUFAs aka omega- fatty acids). Unsaturated FAs either show a cis-form (like the oleic acid depicted, in which the two carbon branches are in the same side) or a trans-form (in which the two pieces of the carbon branches are opposing each other). Trans unsaturated FAs (aka trans-fats) have been already a bad rep because of their detrimental effects on the cardiovascular system (they are suspected to increase LDL levels which are known to contribute in the atherosclerotic plaques formation). Saturated FAs are also having a bad rep because they are also associated with increased risk of cardiovascular diseases, whereas unsaturated FAs (commonly found in “the Mediterranean diet”) are considered healthier.
FAs composition are usually denominated as the following: Cn:m with n referring to the number of carbons (usually an even number), m referring to the number of C=C. In our cases, stearic and oleic acid share the same number of carbon (C18) but the former has no C=C bounds (C18:0) and the latter has a C=C bound (C18:1).
Based on this table, you can see how coconut oil fares to other oils (https://www.chempro.in/fattyacid.htm)
It contains 90% of saturated FAs and 10% unsaturated FAs, whereas most of other oils commonly used in Western countries have at least 50% or more of unsaturated FAs. To give you an idea lard, tallow (beef) and butter contains 40%, 37% and 41% respectively.  You can see how coconut oil is exploding the chart.

But, but this is coming from one study and science has been wrong all the time

If you stick to mainstream media, you will get this impression right. News outlets like to sell single studies as sold and irrefutable evidence and often oversell the claims of that study. Science is never settled, especially on a single study. Many things can go wrong that result in bias. Sometimes, scientists even cut the corners and publish fraudulent data to support their claims (thats what you see a lot with anti-vaccines, anti-GMO papers, climate-deniers, creationism……).
Science build a consensus on the amount of publications and their robustness in their experimental design. When you have an overwhelming majority of papers show you a same trend, arrive to same conclusion on a phenomenon using different approaches and different observations by different groups, you reach a conclusion and set a consensus.
A consensus is only broken once you have new studies that refute the existing claims with more robust and more precise data than the existing literature. This happens very rarely as you have to being in a weight of evidence bigger than the existing literature.

The science on FAs and their effect on cardiovascular diseases is not new, this have been known for over 50 years and keep refining. This consensus built on the detrimental effects of high-fat diet is well-known and served to establish guidelines and public health recommendations. The American Heart Association, the leading association worldwide gathering both basic and clinical scientists as well as any healthcare actors establish guidelines.

The AHA has a clear statement, visible here:
http://news.heart.org/advisory-replacing-saturated-fat-with-healthier-fat-could-lower-cardiovascular-risks/
Replacing saturated fats may help to reduce your risk of cardiovascular events, in addition to an healthy (balanced) diet and physical activity.

The study that made the uproar is available here and comes from the scientific board of the AHA. You can download it for free and you can see another fat composition of different oils:
http://circ.ahajournals.org/content/early/2017/06/15/CIR.0000000000000510

As you can see, coconut oil tops the list of saturated oils and fats, followed by butter and lard. Saturated fats consumption are clearly associated with increased risk of coronary heart diseases (CHD, aka heart attack), replacement with unsaturated fats reduce such risks. Replacement with PUFAs appears even more beneficial. Such effects is not limited to CHDs, but appears involved in other diseases as well (see Figure 4).

In conclusion, dont ditch your coconut oil yet. As small amount, coconut oil is fine. What is not fine was the fad diet that was basically pushing you to switch everything to coconut oil. In my personal opinion, I would say that butter (real unsalted butter like the French “President”, Irish “Kerrygold” or Danish “Lupak” butters; not the things called margarines that were at the basis of the trans-fat problem),  was even a better alternative  than coconut oil.

In conclusion, keep your peanut oil for your deep-frying cooking, keep your canola oil for your dressings and use olive oil for cooking instead of lard and coconut oil. If the taste of coconut oil is good, just add the minimal amount needed to taste.

 

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