Nutrition

Coconut oil for weight loss, does it work or is it just the latest trend?

70% of american people think coconut oil is healthy. Indeed, coconut oil is supposed to have many benefits: it prevents skin aging, cancer, weight gain, it has tooth whitening benefits, it has antibacterial, anti-inflammatory, antimicrobial effects… The list never ends! However, only 37% of nutritionists think coconut oil is healthy[1].

Lsee decided to focus on the possible effects of coconut oil on weight loss: are they real or just the latest fashion ?

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Coconut Oil and Science

What are the main components of coconut oil? Coconut oil is composed of about 85% of saturated fats (among them, 45% of lauric acid) but also vitamins E and K. If saturated fats are often criticized because eating too much of them can increase your blood cholesterol levels, not all of them are bad!

Indeed, lauric acid is the main saturated fat of coconut oil and it is a medium chain fatty acid. Medium-chain triacylglycerols (MCT) go faster into your bloodstream and provide energy more quickly to your cells than long chain fatty acids. Moreover, it is supposed to be harder for your body to store MCTs in adipose tissue. Those are the reasons why scientists did studies about MCTs and weight loss.

Here, we want to mention 6 main studies on which many articles are probably based:

  • MCT consumption increases the total energy expenditure but this effect disappears after 14 days (study done on 12 nonobese women following a balanced diet[2]).
  • MCT consumption increases endogenous oxidation of long chain saturated fatty acids on day 14 (study done on 12 slim women following a balanced diet[3]).
  • MCTs can be an appetite suppressant[4].
  • Coconut oil instead of olive oil causes a bigger weight loss (+1,6kg in 16 weeks – study done on 49 overweight persons following a weight loss program[5]).
  • Coconut oil instead of soybean oil, is not more efficient for weight loss but does promote a reduction in abdominal obesity (minus 1,4 cm in 12 weeks – study done on 40 overweight women[6]-).
  • The effects of coconut oil on weight loss are perhaps greater for men than women[7] (study done on 112 persons for 8 weeks in China).

Outcome of the studies: Mostly done on people following a specific diet, these studies show mixed results. And yet ….

Coconut oil

Coconut Oil for Weight Loss, Myths and Realities…

According to many forums and women’s magazines, coconut oil has miraculous virtues for weight loss. Are the effects real or just a fashionable trend?

If we just consider the results of the studies, a few precautions should be taken before eating coconut oil with a spoon:

– Studies have been done only on short term periods. It is difficult to know if coconut oil is efficient in the long run, particularly as the effects on total energy expenditure disappear after 14 days. Moreover, the effect of coconut oil on weight loss must be put in perspective: only 1,6 more kg lost in 16 weeks is not that much.

– As said before, effects of coconut oil on weight loss was shown on people following a hypocaloric diet. The coconut oil burn effect seems to require an appropriate diet.

– Some studies’ results are very heterogeneous concerning weight loss. Other factors could play a leading role (lifestyle, genetics, metabolism …?).

Currently, coconut oil seems to benefit from a good reputation, maybe also because of its exotic side. So far, the actual facts in its favour are few in number. It is also important to remember that other existing oils have advantages such as rapeseed oil which has a good ratio between omega 6 and omega 3, or olive oil which enables a reduction of the risk of cardiovascular disease.

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All in all, coconut oil for weight loss or not?

There is a real contrast between the benefits of coconut oil revealed in scientific studies and those we can read on weight loss websites. In this article, we tried to see beyond the marketing arguments to find the real effects of coconut oil on weight loss. Because of the current enthusiasm for coconut oil and because of a limited number of scientific studies, it is difficult to take a step back.

Any feedback on coconut oil is welcomed (feel free to comment the article)!

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References :

[1] : http://www.wellandgood.com/good-food/foods-you-think-are-healthy-but-nutritionists-dont/slide/3/

[2] : http://www.ncbi.nlm.nih.gov/pubmed/10232626

[3] : http://www.ncbi.nlm.nih.gov/pubmed/11033985

[4] : http://www.ncbi.nlm.nih.gov/pubmed/9701177

[5] : http://www.ncbi.nlm.nih.gov/pubmed/18326600

[6] : http://f1000.com/prime/717973629

[7] :http://www.ncbi.nlm.nih.gov/pubmed/19786383