Is coconut oil one big fat lie?

In the last few years, coconut oil has gained a reputation as a ‘superfood’ according to many high-profile celebrities, influencers and fitness trainers. Coconut oil has been suggested to be an ‘essential’ oil in the diet and has many claimed health benefits that include improved heart health, brain function, immune function, skin and hair health and even weight loss! But what does science have to say about these claims? Is coconut actually healthy or a just big fat lie! (pardon the pun)

What is coconut oil?

Coconut oil is extracted from coconut flesh and is made up of 99.9% fatty acids of these, 91.9% are saturated fatty acids (SFA), 6.4% are monounsaturated fatty acid acids (MUFA) and 1.5% are polyunsaturated fatty acids (PUFA).

The supposed health benefits are believed to be due to the high amounts of particular saturated fatty acids found in coconut oil such as lauric acid and caprylic acid (1)(2).

Heart Health

Coconut oil has been suggested as a healthy oil that is beneficial for heart health. Advocates have argued that the types of saturated fats found in coconut oil (eg. lauric acid) behave differently to typical saturated fats (eg. butter), thus preventing any negative health effects on heart health… but of course it’s not that simple!

Cholesterol levels are a strong indicator of heart disease. LDL is generally considered to be ‘bad’ cholesterol and HDL is generally considered to be ‘good’ cholesterol. Most studies suggest that coconut oil raises total cholesterol, LDL, and HDL and removing coconut oil from the diet can reduce total cholesterol and LDL, with varying effects on HDL (3).

Another study that assessed 21 research papers, mostly in non-western countries, found similar results in that coconut oil increases total cholesterol but does not lead to negative outcomes for hearth health.

However, these findings may differ when you consider the typical western diet that is high in refined sugars and carbohydrates, saturated fats and trans-fats. This, study suggested that replacing coconut oil with unsaturated fats (eg. hemp seed oil, olive oil, avocado oil) may help to reduce heart disease (4).

Other studies have also demonstrated strong evidence to suggest that increased saturated fat is not associated with heart disease and instead it may be other nutrients in the diet eg. refined carbohydrates, refined sugars, and trans-fats that could explain increased rates of heart disease (5, 6).  

One study in the British Medical Journal explains that in order to reduce heart disease, it’s better to avoid refined sugars and processed foods rather than avoiding saturated fats eg. coconut oil that could explain the increase heart related problems (7).

Take home message here is that although saturated fats (eg. coconut oil) may not be as bad as we think for heart health, consuming lots of polyunsaturated fats in the diet (eg. hemp seed oil, olive oil, and avocado oil) and consuming saturated fats in smaller amounts, while reducing your intake of refined sugars, and processed foods (rich in trans-fats) could be more beneficial in helping to reduce your risk of heart disease.

Weight Loss

Supporters of coconut oil have made claims that specific types of saturated fats called medium-chain triglycerides (MCT’s) found in coconut oil are the reason for some of coconut oil’s potential health benefits (8).  

One of these potential claims of MCT’s effects is weight loss. Results from some animal studies and human studies suggest that the consumption of MCT’s compared to other types of fatty acids in the diet promote weight loss through reduced intake of food and increased energy use (what we call energy balance – the main driver for weight gain/loss).

The theory behind these claims is that MCT’s are ‘instantly’ metabolised by the body rather than being stored, are more satiating (filling) than other fats, and help to speed up our metabolic rate.

However, these claims are yet to be proven as majority of these studies were only done in small groups and many of these studies did not include humans. Currently, there is lack of good quality evidence to suggest that coconut oil can assist with weight loss (9)(10).

Immune boosting effects

The ‘immune-boosting’ properties of coconut oil claimed by advocates have been attributed to lauric acid (found in coconut oil and human breastmilk) and monolaurin, a chemical made from lauric acid that is produced in the body after the consumption of coconut oil (11).

Both monolaurin and lauric acid reportedly have antibacterial and antiviral (anti-virus) properties but this has mostly been demonstrated in vitro (test tubes) or in animal studies (10).

There is some human evidence that suggests that monolaurin may be effective at preventing infections when used topically (12, 13).  

However, due to the lack of human studies, how much monolaurin is produced inside the body from the breakdown of lauric acid is still undecided. Meaning that the anti-bacterial and anti-viral effects of coconut oil remain unknown!

Brain effects

There are claims that coconut oil is beneficial for the treatment of Alzheimer’s disease. Studies have found that a product made mostly of caprylic acid (found in large amounts in coconut oil) may help to improve brain function in Alzheimer’s disease. However, it’s important to note that most of these findings are based on animal studies and only a small number of human studies (14, 15) .

The reason behind these claims is that caprylic acid helps to induce mild ketogenesis, where your brain switches it’s energy source from sugar to fats, producing ketones (16, 17).

While these are interesting results, there seems to be no direct studies looking at the effects of coconut oil on brain function. So, it’s probably a bit too soon to make the claim that coconut oil can improve brain function and treat Alzheimer’s disease.

Hair & Skin health

There are claims of coconut oil being healthy for both hair and skin. You may actually find coconut oil in many sunscreens, however, don’t be fooled as coconut oil has an SPF or around 1. While, the Cancer Council of Australia suggest an SPF of 30 and above for the harsh Australian sun.

One of the health benefits that coconut oil may actually be effective for is as a skin moisturiser. Coconut oil can act as a sealant, by trapping water into the skin to keep it moist. However, according to skin experts, even though coconut has moisturising effects, it is still recommended to use over moisturiser or on damp skin. Coconut oil also contains fatty acids that may be good for the skin (18). 

Coconut oil has also been suggested to moisturise, provide nutrients, kill bacteria and improve circulation of blood in the scalp, with some websites even suggesting slowing down hair loss. While these claims sound amazing, coconut only contains a small amount of nutrients and as discussed, very little evidence of antibacterial properties.

So, what's the bottom line? 

Even though coconut has been claimed to be a superfood by many health experts, and celebrities, the science suggests otherwise. While coconut may not be inherently bad, using large amounts is unlikely to improve heart health, immunity, weight loss, and brain health.

Not to mention that coconut oil contains nine calories per gram, that is very calorie dense that could lead to increased weight gain.

If you did want to use coconut oil, probably best to just use it for flavour in Asian dishes and as a moisturising agent for the skin.

There are plenty of other oils such as olive oil, avocado oil and hemp seed oil that have much better claims to health, so best to use these as much as possible! (19, 20, 21).

If you have any questions or need support with your health, feel free to email our head nutritionist Ben at ben@13seeds.com.au 

Disclaimer:

This article does not constitute medical advice and does not take into consideration your personal circumstances. Please see your medical professional before implementing the above.

References:

1. https://www.gov.uk/government/publications/composition-of-foods-integrated-dataset-cofid
2. https://onlinelibrary.wiley.com/doi/full/10.1111/nbu.12188
3. https://pubmed.ncbi.nlm.nih.gov/23037905/
4. https://academic.oup.com/nutritionreviews/article/74/4/267/1807413
5. https://pubmed.ncbi.nlm.nih.gov/20071648/
6. https://www.bmj.com/content/347/bmj.F6340
7. https://www.bmj.com/content/351/bmj.h3978/rr-11
8. https://pubmed.ncbi.nlm.nih.gov/25387216/
9. https://pubmed.ncbi.nlm.nih.gov/11880549/
10. https://onlinelibrary.wiley.com/doi/full/10.1111/nbu.12188#nbu12188-bib-0004
11. https://pubmed.ncbi.nlm.nih.gov/17211132/
12. https://pubmed.ncbi.nlm.nih.gov/20008774/
13. https://pubmed.ncbi.nlm.nih.gov/25179088/
14. https://pubmed.ncbi.nlm.nih.gov/19664276/
15. https://pubmed.ncbi.nlm.nih.gov/15123336/
16. https://pubmed.ncbi.nlm.nih.gov/25076901/
17. https://pubmed.ncbi.nlm.nih.gov/25301680/
18. https://www.healthline.com/health/coconut-oil-moisturizer#benefits
19. https://www.tandfonline.com/doi/abs/10.1300/J133v02n04_04
20. https://www.mdpi.com/1422-0067/19/3/686
21. https://www.scielo.br/scielo.php?pid=S0103-84782016000400747&script=sci_arttext