A great example of a controversial food is coconut oil. It is generally praised by the media, but some scientists doubt it lives up to the hype.
It has mainly gotten a bad rap because it is very high in saturated fat. But new studies suggest saturated fat is not as unhealthy as previously believed.
Is coconut oil an artery-clogging junk food or a perfectly healthy cooking oil? This article looks at the evidence.
Coconut oil is very different from most other cooking oils and contains a unique composition of fatty acids.
The fatty acids are about 90% saturated. But coconut oil is perhaps most unique for its high content of the saturated fat lauric acid, which makes up around 40% of its total fat content ().
This makes coconut oil highly resistant to oxidation at high heat. For this reason, it is very suitable for high-heat cooking methods like frying ().
Coconut oil is relatively rich in medium-chain fatty acids, containing around 7% caprylic acid and 5% capric acid ().
Epileptic patients on ketogenic diets often use these fats to induce ketosis. However, coconut oil is not suitable for this purpose as it has a relatively poor ketogenic effect (, ).
While lauric acid is often considered a medium-chain fatty acid, scientists debate whether this classification is appropriate.
The next chapter provides a detailed discussion of lauric acid.
Summary Coconut oil is rich in several types of saturated fat that are otherwise uncommon. These include lauric acid and medium-chain fatty acids.
Coconut oil contains about 40% lauric acid.
In comparison, most other cooking oils contain only trace amounts of it. An exception is palm kernel oil, which provides 47% lauric acid ().
Lauric acid is an intermediate between the long-chain and medium-chain fatty acids.
While often considered medium-chain, it is digested and metabolized differently from the true medium-chain fatty acids and has more in common with the long-chain fatty acids (4, , ).
Studies show that lauric acid increases the blood levels of cholesterol, but this is mostly due to an increase in cholesterol bound to high-density lipoproteins (HDL) (, ).
An increase in HDL cholesterol, relative to total cholesterol, has been associated with a reduced risk of heart disease ().
Summary Coconut oil is exceptionally rich in lauric acid, a rare saturated fat that seems to improve the composition of blood lipids.
Studies indicate that regularly eating coconut oil improves the levels of lipids circulating in the blood, potentially reducing the risk of heart disease.
One large, randomized controlled study in 91 middle-aged adults examined the effects of eating 50 grams of coconut oil, butter or extra-virgin olive oil daily for a month ().
The coconut oil diet significantly increased the “good” HDL cholesterol, compared to butter and extra-virgin olive oil.
Similarly to extra-virgin olive oil, coconut oil didn’t increase the “bad” LDL cholesterol ().
Another study in women with abdominal obesity found that coconut oil increased HDL and lowered the LDL to HDL ratio, while soybean oil increased total and LDL cholesterol and decreased HDL ().
These results are somewhat inconsistent with older studies showing that coconut oil raised LDL cholesterol compared to safflower oil, a source of polyunsaturated fat, although it didn’t raise it as much as butter (, ).
Taken together, these studies indicate coconut oil may be protective against heart disease when compared to certain other sources of saturated fat, such as butter and soybean oil.
However, there is yet no evidence that it affects hard endpoints like heart attacks or strokes.
Summary Studies show that coconut oil may raise the levels of the “good” HDL cholesterol, relative to total cholesterol, potentially decreasing the risk of heart disease.
There is some evidence that coconut oil may help you lose weight.
In a study of 40 women with abdominal obesity, coconut oil reduced waist circumference compared to soybean oil while also improving several other health markers ().
Another controlled study in 15 women found that virgin coconut oil reduced appetite compared to extra-virgin olive oil, when added to a mixed breakfast ().
These benefits are possibly due to medium-chain fatty acids, which may potentially lead to a modest decrease in body weight ().
However, scientists have pointed out that the evidence on medium-chain fatty acids cannot be applied to coconut oil ().
Despite some promising evidence, research is still limited and some researchers question coconut oil’s weight loss benefits ().
Summary A few studies suggest coconut oil may reduce belly fat and suppress appetite. But the true weight loss benefits are controversial and only moderate at best.
If coconut fat is unhealthy, you would expect to see some health problems in populations that eat a lot of it.
In the past, populations of indigenous people who got a large percentage of their calorie intake from coconuts were much healthier than many people in Western society.
The Tokelauans, for example, got more than 50% of their calories from coconuts and were the biggest consumers of saturated fat in the world. The Kitavans ate up to 17% of calories as saturated fat, mostly from coconuts.
Both of these populations appeared to have no traces of heart disease despite the high saturated fat intake and were overall in exceptional health (, ).
However, these indigenous people followed healthy lifestyles overall, ate a lot of seafood and fruit, and consumed virtually no processed foods.
It is interesting to note that they relied on coconuts, coconut flesh and coconut cream — not the processed coconut oil you buy in supermarkets today.
Nevertheless, these observational studies indicate that people can stay healthy on a diet high in saturated fat from coconuts (, ).
Just keep in mind that the good health of these indigenous Pacific populations reflected their healthy lifestyle, not necessarily their high coconut intake.
In the end, the benefits of coconut oil probably depend on your overall lifestyle, physical activity and diet. If you follow an unhealthy diet and don’t exercise, a high intake of coconut oil won’t do you any good.
Summary Pacific islanders following indigenous diets ate lots of coconut without any apparent harm to their health. However, their good health probably reflected their healthy lifestyles rather than coconut oil per se.
Although the benefits of coconut oil remain controversial, there is no evidence that a moderate intake of coconut oil is harmful.
On the contrary, it may even improve your cholesterol profile, though it’s currently unknown whether it has any effects on heart disease risk.
These benefits have been attributed to its high content of lauric acid, a unique saturated fat that is otherwise rare in food.
In conclusion, eating coconut oil appears safe and may even improve your health. But as with all cooking oils, make sure to use it in moderation.