Coconut oil…

Apparently it can help you lose weight, stave off all manner of illnesses and even prevent Alzheimer’s disease. Previously shunned for its high saturated fat content, coconut oil has experienced a huge revival in popularity and taken the media by storm. It is now being used in cooking and features in many recipes. It can be found in health food shops and most large supermarkets.   

The costly jars of organic virgin coconut oil we see on the shelves now differ greatly from the trans fat-containing partially-hydrogenated coconut oil found in junk food in the ‘80s. Virgin coconut oil may be better than its junk food predecessor, but is it really a panacea for good health or is it just the best of a bad bunch?

Most commonly used vegetable oils (soya, olive, sunflower and rapeseed oils) contain less than 16 per cent saturated fat (see table below). Butter contains over 50 per cent and coconut oil contains a whopping 86.5 per cent saturated fat!

Like many other fats, coconut oil contains virtually no protein, no carbohydrate and no sugar or fibre. It provides little to no vitamins or minerals with the exception of 0.66mg of vitamin E (considerably less than all the other oils – see table below).

Fatty acid composition of a range of foods

Type of fat (100g)	Coconut oil	Butter	Soya oil	Olive oil	Sunflower oil	Flaxseed oil*	Rapeseed (canola) oil
Total fat (g)	99.9	82.2	99.9	99.9	99.9	99.9	99.9
Saturated fat (g)	86.5	52.1	15.6	14.3	12.0	9.4	6.6
Monounsaturated fat (g)	6.0	20.9	21.3	73.0	20.5	20.2	59.3
Polyunsaturated fat (g)	1.5	2.8	58.8	8.2	63.3	66.0	29.3
Trans fats (g)	Tr	2.9	Tr	0	Tr	Tr	Tr
Vitamin E (mg)	0.66	1.85	16.06	5.10	49.22	17.5	22.21

Source: McCance and Widdowson, 2002, and USDA*.

A quick lesson in cholesterol LDL ‘bad’ cholesterol can build up on the walls of the arteries and increase the risk of heart disease. The lower your LDL cholesterol number, the better it is for your health. The government recommends that levels of LDL should be 3mmol/L or less for healthy adults. HDL ‘good’ cholesterol protects against heart disease by taking the ‘bad’ cholesterol out of the blood and preventing it from building up in the arteries. A higher number for this cholesterol is good. An ideal level HDL is above 1mmol/L. A lower level can increase your risk of heart disease. Total cholesterol is a measure of LDL cholesterol, HDL cholesterol and other lipid (fat) components. The government recommends that total cholesterol levels should be 5mmol/L or less for healthy adults.

Coconut flesh

Like all other plant foods, coconut is cholesterol-free. Although it is a fruit, coconut flesh has a nutritional profile completely different to what you’d expect from a fruit; it is very high (33g per 100g) in fat. Also, unlike most plant foods, most of the fat (nearly 90 per cent) in coconut is saturated – the worst type of fat as it increases cholesterol, which in turn increases the risk of heart disease.

Desiccated coconut (coconut flesh that has been shredded or flaked and dried) has a fat content similar to that of tree nuts (hazelnuts, almonds and Brazil nuts) weighing in at 62g of fat per 100g (see below). However, gram for gram, the fibre content is two to three times that in nuts. Some studies suggest that coconut flakes can lower LDL ‘bad’ cholesterol in people with moderately raised levels (Trinidad et al., 2004). This may be because coconut flakes are a good source of fibre which has cholesterol-lowering properties. Processing coconut to produce oil strips away this protective fibre.

The fat and fibre content of coconut compared to selected fruit and nuts

	Total fat per 100g (g)	Fibre per 100g (g)
Apple	0.1	1.8
Banana	0.3	1.1
Orange	0.1	1.7
Coconut flesh*	33.5	9.0
Dessicated coconut	62.0	13.7
Hazelnut	63.5	6.5
Almond	55.8	7.4
Brazil nut	68.2	4.3

Source: McCance and Widdowson, 2002, and USDA*.

A recent study found that coconut milk (with a fibre content of around 5g per cup) not only lowered the LDL‘bad’ cholesterol, but raised HDL ‘good’ cholesterol levels (Ekanayaka et al., 2013). This suggests that whole coconut (flesh or dried flakes) might offer heart health benefits, but this could simply be down to the high fibre content. Fibre is easily obtained from other fruit and vegetables as well as wholegrain foods and pulses that don’t contain so much fat. The recommended average intake for fibre for adults is 18g per day. To increase your intake choose a high-fibre breakfast cereal (oats or muesli with no added sugar), switch from white bread, pasta and rice to wholegrain bread, pasta and brown rice and ensure you have at least five portions of fruit and vegetables a day.  

The Pacific Islanders Study

A well-cited 1981 study is often used to promote the use of coconut oil. The study focused on the atoll dwellers from two Pacific islands, the Pukapuka and Tokelau, who used coconut as a main source of energy. The study concluded there was no evidence that a high saturated fat intake from coconut had a harmful effect (Prior et al., 1981).

In both populations, every meal contained coconut in some form. The green nut provided the main drink, the mature nut was grated or creamed and small pieces of the flesh were consumed as snacks. In addition, coconut sap was used as a sweetener and a leavening agent in bread and coconut oil was used to fry some foods. Importantly, the Tokelauans consumed almost twice the number of calories from coconut than the Pukapukans (63 per cent compared with 34 per cent) so their intake of saturated fat was considerably higher.    

As might be expected, Tokelauans had higher blood cholesterol levels than Pukapukans. However, cholesterol levels in both populations were substantially lower than the predictions made based on their diets (and fell within the UK government recommended levels for cholesterol in healthy adults). Heart disease was apparently rare among both groups.

Both populations had low intakes of salt, sugar and cholesterol in their diets and consumed a healthy amount of fibre, plant sterols and omega-3 fatty acids. They also had a more active lifestyle and used little tobacco. Interestingly, when Tokelau Islanders moved to New Zealand and experienced a drop in their saturated fat intake, their intake of cholesterol, simple carbohydrates and sugar went up and so did their risk of heart disease. Evidence that whole diet and lifestyle can have a profound effect on health.

The lower than expected cholesterol levels among these islanders might be attributed in part to coconut fibre as well as their healthier (than the typical Western) lifestyle. As stated, coconut flesh and flakes are a good source of fibre which has cholesterol-lowering properties and so may balance out the risk of heart disease and stroke caused by the high saturated fat it contains. This may not be a gamble you need to take given the wide choice we have of good energy-supplying foods packed with fibre but not rich in unhealthy saturated fat. 

What’s the beef with saturated fat?

It is well-documented how saturated fat can have a harmful effect on cholesterol levels and so increase the risk for heart disease (Fernandez and West, 2005). Too much ‘bad’ cholesterol in the bloodstream can cause cholesterol-filled plaques to develop. These deposits not only clog the arteries and slow blood flow, they can break apart and cause a heart attack or stroke.

The Department of Health recommends that saturated fat should contribute no more than 11 per cent of the total energy that we get from food (Department of Health, 1991). Most people in the UK consume more than that. Most saturated fat in the average UK diet comes from: fatty cuts of meat, poultry skin, meat products such as sausages and pies, whole milk and full fat dairy products such as cheese and cream, butter, ghee and lard, coconut oil and palm oil, pastry, cakes and biscuits, sweets and chocolate. These foods that are high in saturated fat raise cholesterol levels in the blood by promoting production of cholesterol in the liver. In fact, saturated fats are recognised as the single dietary factor that has the greatest negative effect on LDL ‘bad’ cholesterol (Hu, et al., 2001).  

Cochrane Reviews are internationally recognised as the highest standard in evidence-based health care, often referred to as the gold standard. A 2012 review from The Cochrane Library analysed 48 studies including over 65,000 participants. It was found that reducing saturated (animal) fat, but not total fat intake, reduced the risk of heart attack and stroke by 14 per cent (Hooper et al., 2012).

Are all saturated fats equal?

Among the saturated fatty acids, lauric, myristic and palmitic acids are considered to be the most hypercholesterolemic (they drive up cholesterol levels the most). They are found in meat, dairy products, eggs and tropical oils (palm and coconut oil). These three fatty acids account for most of the saturated fat in Western diets. They all raise cholesterol but not to the same extent:  

• Myristic acid (14 carbon atoms) is found in palm kernel oil (not to be confused with palm oil which is extracted from the fruit of the plant), coconut oil, butter and it is found in many other animal fats in varying amounts. Myristic acid is the most potent cholesterol-raising fatty acid.
• Palmitic acid (16 carbon atoms) is found in palm kernel oil, butter, cheese, milk and meat.
• Lauric acid (12 carbon atoms) comprises about half of the fatty acid content of coconut fat. It is also found in smaller amounts in human breast milk, cow’s milk and goat’s milk. Lauric acid has around one-third less cholesterol-raising power than palmitic acid (Denke and Grundy, 1992).

Medium and long-chain fatty acids

The length of a saturated fatty acid may affect how potently it raises cholesterol. Fatty acids classed as short-chain have less than six carbon atoms, medium-chain have 6-12 carbon atoms and long-chain have more than 12 carbon atoms. The vast majority of fats we eat, whether they are saturated or unsaturated, or come from animal or plant foods, are composed of long-chain fatty acids. Monounsaturated and polyunsaturated fats are all long chain unsaturated fats. The fat in animal products tends to be mostly made up of long-chained saturated fatty acids which are well-established as being lipidogenic or fat-producing (Ekanayaka et al., 2013). When they are broken down in digestion, long-chain fatty acids are rebuilt into cholesterol and triglycerides (the type of fat found in blood and body fat) which are taken up by cells and transported in the bloodstream to be used for energy or stored as fat.  

Coconut is fairly unique in that around half its fat is made up of medium-chain saturated fatty acids. Some reports suggest that medium-chain fats behave differently in that they are absorbed and transported directly from the stomach to the liver where they are used to supply energy (for example to the brain or heart) and do not become stored as fat. Indeed, some studies suggest that the majority of ingested lauric acid is transported to the liver where it is directly converted to energy and other metabolites rather than being stored as fat (Dayrit, 2014). This means the medium-chain saturated fats in coconut may be easier to burn off than the long-chain fats found in butter and lard. This idea that medium-chain fats are cholesterol-neutral is widely reported despite evidence to the contrary dating back to the 1990’s (Denke and Grundy, 1992; Tholstrup et al., 2004). It is now well-documented that the medium-chain fats in lauric acid can indeed increase cholesterol…

Some studies have found that medium-chain fatty acid consumption increases total cholesterol and LDL cholesterol to the same extent as palm oil. Reductions in HDL ‘good’ cholesterol and no effect on total cholesterol, LDL and HDL have also been observed with medium-chain fatty acids (St-Onge et al., 2008).  Furthermore, other studies show that in contrast with the potential neutral effect on cholesterol, medium-chain fatty acids can increase plasma triglycerides (fats in the blood) in much the same way that long-chain fatty acids do (Tholstrup et al., 2004).

On a varied diet, which contains a range of fats, medium-chain fats tend to be channelled directly to the liver for energy production. However, when the diet contains mostly medium-chain fats, some of these may also be incorporated into the route leading to the production of cholesterol and/or fat deposits (Swift et al., 1990). This may explain some of the conflicting results that are reported in the literature (Dayrit, 2014). It also provides a compelling argument for not limiting your intake of fats to just coconut oil.

Furthermore, the medium-chain saturated fatty acid lauric acid makes up only half the total fat in coconut oil, nearly a third is made up of long-chain saturated fatty acids (myristic and palmitic acids – the major fatty acids found in red meat), the rest is made up of a small amount of monounsaturated and polyunsaturated fats (Ekanayaka et al., 2013).  

Saturated fatty acids in coconut fat

• 45.8 per cent lauric acid – medium-chain fatty acid
• 18.4 per cent myristic acid – long-chain fatty acid
• 8.0 per cent palmitic acid – long-chain fatty acid

Source: Ekanayaka et al., 2013.

Coconut oil, cholesterol and obesity

As stated, studies on the effect of coconut oil and/or lauric acid on cholesterol are contradictory (Dayrit. 2014). One study investigated how coconut oil affected cholesterol in women in the Philippines aged 35-69 who use coconut oil to fry or sauté food (Feranil et al., 2011). The women consumed between 8.4-10.3g of coconut oil each day (a relatively low intake). Their cholesterol levels were measured in blood samples collected after an overnight fast. They found that coconut oil conferred beneficial effects improving HDL ‘good’ cholesterol levels among women who consumed the most oil compared to those consuming the least. The coconut oil did not affect the level of LDL ‘bad’ cholesterol. However, all the women had low HDL to begin with and the positive effect was only seen among the pre-menopausal women.  

A 2009 study found that obese Brazilian women taking 30ml (two tablespoons) of coconut oil once a day, while dieting and exercising over 12 weeks, also had improved levels of HDL ‘good’ cholesterol and a slightly reduced waist measurement compared to similar women taking 30ml of soya bean oil (Assunção, et al., 2009). Soya bean oil is relatively low in saturated fat (around 15 per cent) and over 50 per cent of it is polyunsaturated omega-6 linoleic acid. It contains around 23 per cent monounsaturated oleic acid. Whereas coconut oil is mostly saturated fat and has negligible levels of polyunsaturated fats. So, it might be expected that the group given saturated coconut fat gained weight and their cholesterol got worse, while the group using soya bean oil lost weight and improved their cholesterol. This was not what happened.

In the coconut oil group, HDL increased, LDL increased (although not significantly), and the LDL:HDL ratio improved. The BMI of both groups improved but the coconut group experienced a reduction in waist measurement. In the soya group, total cholesterol, LDL and the LDL:HDL ratio all increased. It was concluded that coconut oil does not cause dyslipidemia (high total or LDL cholesterol levels, or low HDL) and may even promote a reduction in abdominal obesity. It was a curious result given that all women experienced some weight loss, which in itself should have reduced the cholesterol in both groups.  

The authors point out how the women lived in poor socioeconomic conditions and that carbohydrates (potatoes, flour and bread) made up about 70 per cent of their diet compared to just 50-55 per cent of the diet of most Western populations. Fruit and vegetable consumption was practically none and the intake of fibre was just 10g a day. Research shows that people who eat a carbohydrate-rich diet, exhibit higher rates of de novo lipogenesis (converting excess carbohydrates into fats for storage in the body) and are less able to clear LDL ‘bad’ cholesterol from the blood. The authors suggest that these metabolic adaptations induced by their carbohydrate-rich diet could have influenced the results so they cannot be applied to other populations.  

The authors conclude that saturated fats cannot be held responsible as the sole cause of obesity, high total or LDL cholesterol and risk for cardiovascular disease, but that the overall composition of the diet, particularly the fatty acid, cholesterol and antioxidant content, as well as the lifestyle of the individuals, must be taken into consideration. They recommended evaluating the effects of coconut oil over a more prolonged period.

Another study in 2011 looked at the effect of coconut oil on body weight in 20 obese Malay adults (13 women and seven men – a very small number for a study). They were given 30ml of coconut oil per day for four weeks (Liau et al., 2011). There was a significant but small reduction in waist circumference (2.6cm) among the seven men, but no reduction was observed in the women. There was no change in the lipid profile and no other measures of body weight showed any difference. The authors said that this trial was too small and too short in duration to draw significant conclusions and suggest that a properly designed randomised placebo-controlled trial should be performed to further confirm the beneficial effects of virgin coconut oil.

A randomised crossover test investigated the effects of a high-protein Malaysian diet prepared with three types of cooking oil: palm olein (a liquid form of palm oil containing saturated palmitic acid), coconut oil (rich in saturated lauric and myristic acids) and virgin olive oil (containing monounsaturated oleic acid) in 45 healthy adults (Voon et al., 2011). The diets consisted of 30 per cent of calories from fat, 20 per cent from protein and around 50 per cent from carbohydrates. The three dietary regimes were each followed for five weeks. Results showed that the postprandial (after eating a meal) total cholesterol for palm olein and olive oil diets and all fasting lipid indexes (total cholesterol, LDL and HDL) for the olive oil diet were significantly lower than for the coconut oil diet.

In a 2014 randomised crossover study, the effect of medium chain fatty acids on cholesterol were investigated in 28 obese, insulin-resistant men given either 20g of medium-chained fatty acids (modified coconut and/or palm kernel oil), compared with 20g corn oil for four weeks (Tremblay et al., 2014). Results showed that the medium chain fats had no beneficial or harmful effects on cholesterol levels. The authors suggest (in agreement with Swift’s comments – see above) it may be possible that a high dietary intake of medium chain fatty acids (over 60g per day or 20 per cent of total energy intake) is required to elicit adverse changes in cholesterol. It may be a similar scenario to the studies we have seen on red wine, a small amount can be beneficial, but it is well-accepted how harmful large amounts are! So many food and health stories reach the same conclusion (with the exception of fruit and vegetables) moderation is key!

The Hunger Games

High-fat diets are associated with obesity. The weak satiety response (the fact that fatty food may not make you feel as full as protein) is thought to play a role. Some evidence supports the idea that diets rich in medium chain fatty acids can supress the appetite better than diets rich in long-chain fats (found in meat and dairy). This may be because as stated, medium-chain fatty acids do not always enter the lymphatic circulation but are transported to the liver directly to provide energy. This theory was put to the test in a study of 18 lean men given 52g of fat as either: short chain fatty acids (dairy foods), medium-chain fats (coconut oil) or long-chain fats (beef tallow) in a randomised, cross-over study (Poppitt et al., 2010). All participants tried each type of fat for three days. They were asked to rate their appetite, how hungry or satisfied they felt after each trial. There was no significant effect of fatty acid chain length on ratings of hunger, fullness or satisfaction. It was concluded that there was no evidence that fatty acid chain length has any effect on measures of appetite in lean men.

Cooking with coconut oil

Coconut oil is the principal cooking fat used by the people of Kerala in India. Replacing saturated fat with polyunsaturated fat is known to be effective in reducing cholesterol levels but not much is known about the effect of such substitutions on the fatty acid composition of arterial plaques (the fatty deposits that build up on artery walls that lead to heart disease).

One study looked at the effects of cooking with coconut oil compared to sunflower oil in people with heart disease (Palazhy et al.¸2012). The change in cooking oil did affect which fats were present in the blood; sunflower oil consumers had higher levels of polyunsaturated linoleic acid, while coconut oil users had higher levels of the saturated fat myristic acid. However, there was no difference in the type of fat deposited in the arteries; long-chain saturated fats dominated the lipid content of plaques of all participants. Traditional Kerala food is vegetarian but most of Kerala’s Hindus (except its Brahmin community), eat fish, chicken, beef, pork, eggs and mutton. When it came to the cause of the plaque build-up in the arteries, the intake of saturated fats from animal sources is likely to be a main source of the problem. Vegetarians are known to have a significantly lower risk of heart disease; vegetarians have lower cholesterol, blood pressure and rates of type 2 diabetes (Craig et al., 2009).Vegetarians have a 32 per cent lower risk of heart disease (Crowe et al., 2013).  

Criticism of coconut studies

Critics point out that the methodologies of most studies demonstrating coconut oil’s health and weight-loss benefits tend to be performed for short periods of time (4-12 weeks), with small numbers of study participants (just 20-40), and many of the results have not been significant enough to prove long-term benefit of coconut oil consumption. In comparison, the research supporting the benefits of unsaturated fatty acids, particularly monounsaturated and omega-3 fatty acids, are much better-established. This is why all major health organisations (the World Health Organisation, the American Dietetic Association, the Dietitians of Canada, the British Dietetic Association, American Heart Association, the British Heart Foundation, the World Heart Federation, the British National Health Service, the United States Food and Drug Administration and the European Food Safety Authority) agree that saturated fat is a risk factor for heart disease. The World health Organisation recommends moving away from animal fats towards healthy plant-based fats found in avocados, nuts, seeds and plant-based oils.

Most common fats contain nine calories per gram (more than double the number of calories per gram of carbohydrate or protein). Too many calories can prevent weight loss and lead to an increase in weight which increases in the risk of heart disease. Many of the coconut oil studies involved supplementation of about 30ml (30g) of coconut oil, which contains around 270 calories. For people looking to lose weight, 270 calories of fat per day is quite substantial to say the least! The government say the average man should aim to have no more than 30g of saturated fat a day and the average woman, no more than 20g of saturated fat a day. So weight loss studies that routinely use 30g of fat per day are not very helpful.

Alzheimer’s and coconut oil

It has been suggested that coconut oil may even help treat or slow the progression of Alzheimer’s disease. As stated, there needs to be a much more substantial body of evidence of benefit before these claims can be taken seriously. On balance, most of these claims are a mixture of sheer make-believe, anecdotal evidence, pseudoscience and poor reporting of a limited number of studies (many of which were conducted on animals and bear no relevance to human health).

Dr Mercola (linked to the infamous Weston A Price Foundation who claim that saturated animal fat is essential for good health and that animal fat intake and high cholesterol levels have no link with heart disease or cancer!) says coconut oil is the smartest choice for cooking, is good for your heart, contains the kind of fat found in mothers’ milk, enhances immunity and helps with weight loss. And of course he sells it.

Various other ‘natural health’ websites say coconut oil can prevent and reverse Alzheimer’s disease. Predictably, this hype comes from anecdotal evidence and laboratory experiments using mouse cells which bear no relevance to humans. The Alzheimer’s Association says: “A few people have reported that coconut oil helped the person with Alzheimer’s, but there’s never been any clinical testing of coconut oil for Alzheimer’s, and there’s no scientific evidence that it helps…” (Alzheimer’s Association, 2015).

In a recent review of the role of coconut for the prevention and treatment of Alzheimer’s disease published in the British Journal of Nutrition it was concluded that: “It must be emphasised that the use of coconut oil to treat or prevent AD [Alzheimer’s disease] is not supported by any peer-reviewed large cohort clinical data; any positive findings are based on small clinical trials and on anecdotal evidence; however, coconut remains a compound of interest requiring further investigation.” (Fernando et al., 2015).

Further health claims

All manner of other health claims have been made for coconut oil including how it can help. Some have an element of truth in them, others none at all:

Convincing evidence	Provides energy (all fat does this!)
Some evidence	Treats cold sores (Coconut oil possesses some antiviral properties but more research is needed) Boosts metabolism (some short-term, small studies show when eaten in moderation compared to other saturated fats) Heals burns (limited evidence) Blocks UV rays (may have a very low SPF but difficult to measure and therefore unreliable to use as sunscreen) Treats acne (some evidence for the antimicrobial properties of lauric acid but may require a delivery system rather than just spreading oil on your face)
No evidence	Balances hormones (there is no clinical evidence for this, in fact coconut oil may increase insulin resistance) Balances blood sugar (anecdotal evidence only) Boosts brain function (no clinical evidence) Treats ear aches and infection (no clinical evidence and should NOT be used if used if the eardrum is damaged) Treats stomach ulcers (anecdotal evidence) Remove warts (no clinical evidence) Alleviate swelling and soothe pain of haemorrhoids (no clinical evidence)

 

What’s the smoke point?

Another selling point for coconut oil is that it is reputed to have a high smoke point (that’s when the fats in the oil break down or oxidise, creating harmful free radicals). However, this simply isn’t the case; many other oils have a higher smoke point (see below). In fact, coconut oil has a relatively low smoke point compared to other commonly used cooking fats.   

Type of oil	Smoke point (°C)
Sunflower	277
Soya	238
Rapeseed	204
Olive	193
Coconut	177
Flaxseed (linseed)	107

Sources: Katragadda et al., 2010 and Wolke, 2007. 

Conclusion

Like most ‘magic bullet’ food and health stories, there may be an element of truth in some claims made about coconut oil. Overall, it appears that the medium-chain fats in coconut oil can play a role in raising HDL. However, coconut oil is still a significant source of calories (115-120 calories per tablespoon), increases total cholesterol levels, especially compared to unsaturated fats found in olive and rapeseed oil, avocados, nuts and seeds. Enthusiasts appear to have extrapolated the potential benefits exaggerating them beyond anything the science can confirm.   

Coconut oil may be beneficial when used to replace saturated animal fats (butter and lard) and hydrogenated fats which contain unhealthy trans-fats. Indeed, once it was realised how harmful trans fats are, coconut oil and palm oil became the fats of choice to replace the hydrogenated vegetable oils used in food manufacturing where hard fats were required (de Roos et al., 2001). This is why we now see palm fat and coconut fat in margarine and other processed foods. Just because something is not as bad for you as butter or lard, doesn’t necessarily make it a health food.

What we do know however though, is that replacing saturated fats with unsaturated fats like vegetable oil, olive oil, flaxseed and rapeseed oil, and their spreads, has been shown as an effective way to help reduce LDL and total cholesterol levels, so choosing these fats is a healthier choice. Many unsaturated oils (such as olive and flaxseed oil), are shown to increase HDL, lower LDL and improve cholesterol/HDL ratio all at the same time. The American Heart Association recommends limiting all saturated fats including those from palm and coconut oil (regardless of whether or not they contain medium-chain fats) because of their association with an increased risk for heart disease.   

While some benefits of coconut oil may exist when replacing other types of fats (especially butter and lard or hydrogenated, trans-fat containing fats), it seems unlikely that including additional coconut oil in the diet would be beneficial. Too much fat in any form is not healthy. It is the total diet or overall eating pattern that is most important in disease prevention and achieving good health. It is better to eat a diet with a variety than to concentrate on individual foods as the key to good health.

Walter Willett, MD, chair of the Department of Nutrition at the Harvard School for Public Health sums it up nicely: “Most of the research so far has consisted of short-term studies to examine its effect on cholesterol levels. We don’t really know how coconut oil affects heart disease, and I don’t think coconut oil is as healthful as vegetable oils like olive oil and soybean oil, which are mainly unsaturated fat and therefore both lower LDL and increase HDL.” (Willett, 2011).

Coconut oil’s HDL-boosting effect may make it ‘less bad’ than its high saturated fat cousins (butter and lard), but it is still not the best choice among the many available oils to reduce the risk of heart disease. Compared to other saturated fats it may be the best of a bad bunch but you are better off replacing saturated fats with healthier unsaturated vegetable oils such as olive oil and rapeseed oil for cooking and flaxseed oil for sauces and dressing.

 

References

Alzheimer’s Association, 2015. Alternative treatments [online]. Available from: www.alz.org/alzheimers_disease_alternative_treatments.asp Accessed June 22 2015.

Assunção ML et al., 2009. Effects of dietary coconut oil on the biochemical and anthropometric profiles of women presenting abdominal obesity. Lipids. 44 (7) 593-601. 

Craig et al.,American Dietetic Association. 2009. Position of the American Dietetic Association: vegetarian diets. Journal of the American Dietetic Association. 109 (7) 1266-1282.

Crowe et al., 2013. Risk of hospitalization or death from ischemic heart disease among British vegetarians and nonvegetarians: results from the EPIC-Oxford cohort study. American Journal of Clinical Nutrition. 97 (3) 597-603.

Dayrit. 2014. The Properties of Lauric Acid and Their Significance in Coconut Oil. Journal of the American Oil Chemists’ Society. Volume 92, Issue 1, 1-15.

Denke and Grundy, 1992. Comparison of effects of lauric acid and palmitic acid on plasma lipids and lipoproteins. American Journal of Clinical Nutrition. 56 (5) 895-898.

Department of Health, 1991. Dietary Reference Values for Food Energy and Nutrients for the United Kingdom. London.

de Roos et al., 2001. Consumption of a solid fat rich in lauric acid results in a more favorable serum lipid profile in healthy men and women than consumption of a solid fat rich in trans-fatty acids. Journal of Nutrition. 131 (2) 242-245.

Ekanayaka et al., 2013. Impact of a traditional dietary supplement with coconut milk and soya milk on the lipid profile in normal free living subjects. Journal of Nutritional Metabolism. 481068.   

Feranil et al., 2011. Coconut oil is associated with a beneficial lipid profile in pre-menopausal women in the Philippines. Asia Pacific Journal of Clinical Nutrition. 20 (2) 190-195.

Fernando et al., 2015. The role of dietary coconut for the prevention and treatment of Alzheimer’s disease: potential mechanisms of action. British Journal of Nutrition. 22 1-14.

Hooper et al., 2012. Reduced or modified dietary fat for preventing cardiovascular disease. Cochrane Database of Systematic Reviews. 5:CD002137.

Hu, et al., 2001. Types of dietary fat and risk of coronary heart disease: a critical review. Journal of the American College of Nutrition. 20, 5-19.  

Katragadda et al., 2010. Emissions of volatile aldehydes from heated cooking oils. Food Chemistry. 120: 59.

Liau et al.,2011. An Open-Label Pilot Study to Assess the Efficacy and Safety of Virgin Coconut Oil in Reducing Visceral Adiposity. ISRN Pharmacology. 949686.

McCance and Widdowson’s The Composition of Foods, 6th summary edition. 2002. Cambridge, England, Royal Society of Chemistry.

Melnick M, 2011. Is Coconut Oil Really All It’s Cracked Up To Be? Huffington Post [online]. Available from: www.huffingtonpost.com/2014/04/22/coconut-oil-healthy_n_5167057.html Accessed June 22 2015.

Palazhy et al.¸2012. Composition of plasma and atheromatous plaque among coronary artery disease subjects consuming coconut oil or sunflower oil as the cooking medium. Journal of the American College of Nutrition. 31 (6) 392-396.

Poppitt et al., 2010. Fatty acid chain length, postprandial satiety and food intake in lean men. Physiology and Behaviour. 101 (1) 161-167.

Poppitt et al., 2010. Fatty acid chain length, postprandial satiety and food intake in lean men. Physiology and Behaviour. 101 (1) 161-167.

Prior et al., 1981. Cholesterol, coconuts, and diet on Polynesian atolls: a natural experiment: the Pukapuka and Tokelau Island studies. America Journal of Clinical Nutrition. 34 (8), 1552-1561.

St-Onge et al.,, 2008. Medium chain triglyceride oil consumption as part of a weight loss diet does not lead to an adverse metabolic profile when compared to olive oil. Journal of the American College Nutrition. 27 (5) 547-552.

Swift  et al., 1990.Medium-chain fatty acids: evidence for incorporation into chylomicron triglycerides in humans. American Journal of Clinical Nutrition 52, 834-836.

Tholstrup et al., 2004. Effects of medium-chain fatty acids and oleic acid on blood lipids, lipoproteins, glucose, insulin, and lipid transfer protein activities. American Journal of Clinical Nutrition. 79 (4) 564-569.

Tremblay et al., 2014. Dietary medium-chain triglyceride supplementation has no effect on apolipoprotein B-48 and apolipoprotein B-100 kinetics in insulin-resistant men. American Journal of Clinical Nutrition. 99 (1) 54-61.

Trinidad et al., 2004. The cholesterol-lowering effect of coconut flakes in humans with moderately raised serum cholesterol. Journal of Medicinal Food. 7 (2) 136-40.

USDA, 2014. Flaxseed oil [online]. Available from: http://nutritiondata.self.com/facts/fats-and-oils/7554/2/ Accessed July 7 2015.

USDA, 2014. Nuts, coconut meat, raw [online]. Available from: http://nutritiondata.self.com/facts/nut-and-seed-products/3106/2 [Accessed July 7 2015].

Voon et al., 2011. Diets high in palmitic acid (16:0), lauric and myristic acids (12:0 + 14:0), or oleic acid (18:1) do not alter postprandial or fasting plasma homocysteine and inflammatory markers in healthy Malaysian adults. American Journal of Clinical Nutrition. 94 (6) 1451-1457.

WHO, 2003. Global strategy on diet, physical activity and health. [online] Available from: www.who.int/dietphysicalactivity/media/en/gsfs_general.pdf  [Accessed 3 July 2015].

Willet W, 2011. Ask the doctor; coconut oil [online]. Available from:  www.health.harvard.edu/staying-healthy/coconut-oil Accessed June 22 2015.

Wolke, Robert L. (May 16, 2007). Where There’s Smoke, There’s a Fryer. The Washington Post [online]. Available from: www.washingtonpost.com/wp-dyn/content/article/2007/05/15/AR2007051500398.html [Accessed June 22 2015].