Over the years there have been many foods labelled as ‘Superfoods’. They come with longs lists of health claims and you find yourself being convinced that if you eat that food, you’ll be cured of everything. Sadly, a lot of the time these claims don’t hold up when proper scientific studies are carried out on them. Coconut oil and coconut products such as coconut milk and coconut water are no different. Between 2011 and 2015 what I would refer to as the ‘Coconut craze’ really kicked off with claims that using coconut oil would help with weight loss due to it containing Medium Chain Fats, or MCT’s (Dewey, 2018). Fats are basically made of 1 glycerol and 3 fatty acid chains as shown below
Image 1: Fat molecule (Lipids | Biology, n.d.)
Those fatty acid chains can be Long Chain Triglycerides (LCT’s) or Medium Chain Triglycerides (MCT’s) depending on how many carbon and hydrogen atoms (the C’s and H’s on the diagram above) there are. There have been some studies done on MCT’s that showed health benefits, and coconut does contain some MCT’s, but it’s mainly made from two LCT Lauric acid and Meristic acid, which have both been linked to raising LDL cholesterol (the bad cholesterol that clogs up your arteries) (Ng et al., 2001). Only 10% of coconut oils fat content is from MCT’s, the rest is LCT’s found in meat and dairy (Ng et al., 2001). If you read my previous blog about fats The importance of Fats you’ll know that saturated fats are the fats we want to avoid as much as possible, and coconut oil is 100% fat with 92% of that fat being saturated (T H Chan, 2018) (Jayawardena et al., 2020). In fact, in 2017 the American Heart Association advised replacing saturated fat oils including coconut oil, with unsaturated oils (Dewey, 2018). Below is a table showing the nutritional information from coconut oil, coconut milk, coconut water and raw coconut flesh
Table 1: Nutritional value of coconut oil, coconut milk, coconut water and raw coconut flesh (Nutrition facts for Nuts, raw, coconut meat, recommended daily values and analysis., n.d.)
|Nutrient||Coconut oil 1tbsp||Coconut milk 1tbsp||Coconut water 1tbsp||100g raw coconut meat|
|Of which are sugars||0g||0.5g||0.4g||6.2g|
|Iron||0||1% of RDA||0||2.43mg|
|Magnesium||0||1% of RDA||0||32mg|
Let’s first look at the studies carried out on coconut oil and its effect on weight. What’s refereed to as an ‘Open label pilot study’ was carried out on twenty men and women. ‘Open label’ means there was no placebo, the participants knew what they were getting, which was two tablespoons of coconut oil per day for one month. There also was no control group to compare the experiment group against when it came to analyse the results. The study showed that the men seemed to lose approximately 1 inch from their waist (Liau et al., 2011). However, dietary studies have shown that when people know their eating habits are being observed, and that they are going to be weighed and measured, they tend to eat less calories and eat healthier than they usually would (Robinson et al., 2015). So, the men losing some inches around the waist could have been due to them reducing their overall calorie intake and eating healthier for that month, nothing to do with the coconut oil at all! Another study carried out in 2015 gave 100 men and women one tablespoon of coconut oil per day for three months. This study had a control group who didn’t get any coconut oil. The coconut oil group lost an average of 1 inch from their waist after the three months, but the group that got no coconut oil didn’t receive a placebo so they were basically comparing taking one tablespoon of coconut oil per day to taking nothing (Cardoso et al., 2015). It was also suggested to the coconut oil group that they take their oil with fruit, this would increase the individuals fruit intake (Cardoso et al., 2015). Studies have shown that eating more fruit has an anti-obesity effect (Sharma et al., 2016). In another study taking two tablespoons of coconut oil per day was compared to taking two tablespoons of soybean oil per day. No significant difference in the waistline of the participants was found. However, the group taking the coconut oil were found to have a significant increase in insulin resistance (Assunção et al., 2009). Read my blog on fats which will explain how a diet high in saturated fats can cause insulin resistance which can lead to developing type two diabetes The importance of fat. The people taking part in this study (both the coconut oil group and the soybean oil group) were instructed to follow a well-balanced diet low in animal fats and refined carbs, and increased consumption of fruits and vegetables. They also took part in four thirty minute exercise sessions per week with a trainer, so the fact that only the coconut oil group showed increased insulin resistance makes it clear that it was very likely the high saturated fat content of the coconut oil causing it (Assunção et al., 2009). Another study carried out in 2017 also showed that taking coconut oil had no significant effect of reducing weight, waist measurement, total fat, belly fat or bum fat on post-menopausal women (Harris et al., 2017). Basically, companies that sell coconut oil and coconut products mainly use evidence from studies carried out on native islanders, who eat a lot of coconuts. But the islanders also eat a mainly plant based diet, and they don’t eat coconut oil, they eat the whole coconut. One of those studies concluded that Pacific islanders who ate more traditional coconut based diets were slimmer and healthier than those who ate a more modern ‘western’ diet (DiBello et al., 2009). Of course, they were! The ‘modern diet’ they referred to consisted of sausages, eggs, processed foods rich in refined carbohydrates (white rice, crisps etc), instant noodle soup and pancakes. So of course, the islanders consuming a diet of whole plant foods, no refined carbohydrates or processed foods, are going to be slimmer and healthier!
Next, we’ll look at the effect coconut oil has on cholesterol. We know saturated fat has an adverse effect on our cholesterol levels, and as I mentioned above, coconut is about 9% saturated fat. A meta-analysis (that’s basically a study that uses multiple studies that had been carried out by someone else, this one used twelve studies), showed that when compared to plant and animal oils, coconut oil significantly raised HDL cholesterol (good cholesterol). With regards to LDL cholesterol (bad cholesterol), compared to plant oils it increased it, but compared to animal oil it lowered it (Teng et al., 2020). This basically means that if you were to rate oils with regards to how bad they are for your cholesterol levels; coconut oil would be in the middle. Not as bad as animal oils, but not as good as plant oils. Another study showed that coconut oil significantly increased Total cholesterol by 15.42mg/dL (normal is approximately 200mg/dL for adults (Goldman, 2020)). LDL cholesterol (bad cholesterol) increased by 10.14mg/dL (normal is less than 100mg/dL (Goldman, 2020)). However, coconut oil seemed to decease HbA1c (Jayawardena et al., 2020). This is your average blood sugar levels over a period of two to three months. A high HbA1c can be an indicator for pre-diabetes or diabetes. High cholesterol levels can lead to Coronary Vascular Disease (CVD). CVD is especially prominent in south Asians. A diet high in saturated increases LDL cholesterol, a diet high in saturated fat is associated with approximately 31% of CVD and 11% of stroke worldwide (Jayawardena et al., 2020). There have been many more studies that have shown that coconut oil raisesTotal cholesterol and LDL cholesterol, and so increases the risk of developing CVD (Heber et al., 1992; Mendis et al., 1989; Mendis and Kumarasundaram, 1990). With all these studies telling us that coconut oil isn’t so good for us, why would people think otherwise? Because, there have been other studies that have pretty much given opposite results! One randomized clinical study showed that when compared to olive oil, coconut oil doesn’t raise LDL cholesterol, and that it significantly raises HDL cholesterol (good cholesterol) compared with butter and olive oil (Khaw et al., 2018). Another study showed that when coconut oil was used as a cooking oil over a period of two years it didn’t increase the risk factors for developing CVD (Vijayakumar et al., 2016). There are also many inconclusive studies on coconut oil and whether or not it increases your risk for developing CVD. There are no studies that show that coconut oil has any beneficial effects on heart health, just studies that show it has adverse effects on heart health, and studies that show it has no effects, good or bad (Sacks Frank M., 2020). Yet, a survey carried out in 2017 showed that over 72% of Americans viewed coconut oil as a healthy food (Sacks Frank M., 2020).
Companies who make food products from coconuts use what is called epidemiological evidence when claiming the health benefits of their food product (Eyres et al., 2016). Epidemiological studies are used to see how often illness and disease occurs in a specific population compared to other populations, and why. The populations the studies used to claim that coconut oil and coconut milk has no adverse health effects are done on populations that consume traditional island diets consisting of large amounts of coconut. One of these studies was carried out on people living on the Melanesian islands (Lindeberg and Lundh, 1993). Their diet consisted of cultivated boiled tubers (yams, sweet potato, taro), fruits (banana, pineapple, mango, guava, watermelon, pumkin), leaves, nuts, tapioca, maize, beans, fish and 80-300g of whole raw coconut, not coconut oil. As well as that, these islanders’ diets contain no red meat or dairy so are generally low in saturated fats, full of fibre from all the fruits and vegetables, and contain no processed foods. This is probably the reason why there is no strokes or heart disease. Another study was done, this time on people living on the Pukapuka and Tokelau islands. Their diets are made up of 63% coconut…and they have high cholesterol. The rest of their diet consists of 87% plant based foods (fruit, vegetables, nut, seeds, wholegrains), with meat, chicken, eggs and alcohol consumed very seldomly, and no dairy (Prior et al., 1981). There was no clinical research done on their disease rates, but even if research was carried out on their disease rates, they were consuming whole coconut, not coconut oil.
Thinking that just because whole coconut is healthy so are products made from it like coconut oil and coconut milk is the same as thinking chips and crisps are healthy because they are made from potatoes, which are vegetables. Or the sugar industry claiming sugar is good from you because it can be found in fruit. The more a food is processed, and the more nutrients are stripped away, the less heathy it becomes. When coconut oil is made the fibre and the protein is removed leaving only fat (Padmakumaran Nair et al., 1999).
Just to prove this, there was a study carried out that tested the effects of coconut flakes (that’s raw coconut shaved into flakes, so they still contain all the nutrients), on people with moderately high cholesterol (Trinidad et al., 2004). Results showed that after giving one group the coconut flakes with 15% fibre there was a 6.9% drop in Total cholesterol, and giving another group flakes with 25% fibre there was a 10.8% reduction in Total cholesterol (Trinidad et al., 2004). Another study looked at the effects of fresh coconut kernels, still containing protein, had on cholesterol levels (Padmakumaran Nair et al., 1999). The results showed a decrease in Total cholesterol and an improvement to the LDL:HDL ratio (Padmakumaran Nair et al., 1999)(the HDL levels should be higher than the LDL levels). In a coconut shell :-D, popular belief egged on by the coconut industry that cocnut oil is healthy is not supported by scientific data (Ng et al., 2001)
Now looking at coconut milk. It can be used instead of cream or dairy to make dishes creamier. However, frequent consumption of coconut milk increases the risk of vascular disease in adults (Darjoko and Sihombing, 2015). In another study three different meals were tested on three groups of people. Group one got a western high fat diet which consisted of a sausage and egg McMuffin, two hash brownies and a non-caffeinated drink. Group two got a Local high fat meal (from Singapore) which consisted of rice cooked in coconut milk, anchovies and an egg. The third meal was an unhealthy low-fat meal which consisted of sugary breakfast cereal with skimmed milk and carrot juice. Meal one and two had the same adverse effects on artery function, whereas the high sugar low fat meal had no adverse effect on artery function (Ng et al., 2001). In 2017 the American Heart Association made a recommendation to avoid coconut oil as much as other animal foods high in saturated fats (Freeman et al., 2017).
Finally, there was only one study I could find describing any health benefits of coconut water. It claimed that coconut waster helps treat depression…when I read the method of the study things started to look a bit dodgy to say the least! Basically, this study was carried out on mice, not humans. The mice were subjected to what’s refereed to as a ‘Forced swim test’, and it is exactly what it sounds like. The mice are dropped into a container of water and then forced to swim. The mice in the experiment group were given young coconut water before they were dropped into the water, and then the time it took them to stop struggling and just float was recorded. The test showed the mice given young coconut water stopped struggling quicker than the control group who got no coconut water (Rao and Najam, 2016). To quote the conclusion of this study “In forced swim test, young coconut water showed significant increase in swimming time that demonstrated antidepressant activity of young coconut water”(Rao and Najam, 2016). Needless to say,I would take that claim with a pinch of salt. Looking back at table one with the nutritional information for coconut water, it could be good to prevent dehydration when doing intense exercise as it contains sodium, potassium and a little bit of carbohydrate, but is till low calorie and won’t cause indigestion like eating solid food before or during exercise would. Water with a little bit of diluted juice and a pinch of salt would do the same thing though.
In conclusion, I believe that like most foods in its whole natural form coconut isn’t the worst food and does have some health benefits because of its high fibre and protein content. However, coconut oil and coconut milk take most if not all the fibre and protein out leaving only fat, which is mainly saturated. Don’t use them thinking they will improve your health. Use them in moderation with a healthy diet and you should be fine.
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