Guest blogger Abbie Reilly (BSc Nutrition)
When I first started my nutrition degree, I would’ve considered myself as being a very well researched, up-to-date, and scientifically orientated health enthusiast commonly consuming coconut oil. I really cannot remember why I thought that coconut oil was good for me, I think the solid evidence was ‘it just is, alright!’, sound familiar? So naturally, I went running out the door to get my hands on this ‘superfood’ to achieve all of the magical claims it is said to have.
It wasn’t until I started to understand labels that I fully grasped how much of a sucker I was, this miracle oil couldn’t possibly be 91% saturated fat, could it? Even through reading this, with the red flags going off in my head, I honestly thought ‘it must be a different kind of saturated fat, like the healthy kind’. But I was wrong!!! There aren’t any good kinds of saturated fat, it doesn’t matter what any insta blogger says, the highly credible science behind the Australian Guide to Healthy Eating does not support this. (For more information, follow this link).
Basically, the idea behind the metabolism boosting and fat-fighting effects of coconut oil is in its composition. For a little bit of context: there are many different types of fatty acids that make up fats like butter, avocado, and olive oil. You may have heard these different types of fatty acids talked about in terms of ‘good’ and ‘bad’ fats? Without going into to too much detail, coconut oil contains a high amount of medium chain fatty acids that are metabolised differently from these other fatty acids, for example, long chain fatty acids that are found in oils such as olive. The result of this difference is an increase in metabolic rate and therefore increased energy expenditure of maximum 5%, depending upon dose consumed.
So really the question becomes, how on earth do these rumours spread if someone somewhere didn’t do research on this topic? Well they did, and as much as I would love the claims behind coconut oil to be accurate, the evidence is seriously flawed. I won’t bore you too much but simply many studies claiming weight loss abilities actually altered a subject’s diet (decreased their kj intake) when testing coconut oil’s effect (so was it coconut oil or diet?) and often didn’t even use coconut oil in the study but use a similar oil instead (close enough isn’t quite good enough sorry).
Many studies report a satiety effects of coconut oil leaving one ‘fuller for longer’. Through the consumption of a recommended dose of coconut oil such as two tablespoons, a stronger sense of fullness can be felt, that can lead to decreased dietary intake. However, there is sound evidence the effect that ALL fats have on delaying digestion and gastric emptying, aiding delay of carbohydrate breakdown and the slower release of glucose (lowering GI) into the bloodstream. So by default based on the fact that coconut oil is a fat (and this is true for all other fats for that matter) coconut oil can be said to make one feel ‘fuller for longer’.
But the question is, what place does this recommendation hold in the diets of NORMAL people? This claim, if correct, may have some benefits if eating tablespoons of oils were part of a regular diet. I’m not going to speak for everyone, but have you ever in your life regularly taken two tablespoons of oil or butter straight? I’m guessing not, therefore I feel this recommendation holds no place in a regular diet. Just adding a few tablespoons of coconut oil into the diet will add an extra 1,300 kilojoules (kJ) on top of the regular daily energy intake when other foods are not removed from the diet. By this logic, if you are eating a fixed amount of kilojoules and then add coconut oil on top of that, then it is likely to make you gain weight, not lose.
The main effect that has been mentioned is coconut oils ability to raise metabolic rate by up to 5%. To put this into real life perspective, in Australia the average daily energy requirement is 8,700 kJ per day. The maximum amount of benefit from two tablespoons of coconut oil would raise metabolism by just 435 kJ but it costs an additional 1,300 kJ just to achieve this metabolic effect. Therefore, put simply, an individual will actually be consuming more net energy in the long run, which would actually lead to weight gain. It is suggested that coconut oil should be consumed in combination with a healthy, real-food based weight loss diet as a replacement option for other food components of the same nature, not as an addition on top of a diet to gain unrealistic weight loss. Just like most foods there is nothing wrong with coconut oil if consumed in moderation, I know I love a bit of coconut oil fried chicken, but don’t expect it to work any of its claimed ‘miracles’ on its own.
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