Hailed and marketed as a super-healthy cooking alternative, coconut oil has been under increased scrutiny lately. Now the science is clear – don’t believe the hype.

Coconut oil’s image as the “good” oil saw it stocked in health food shops and supermarkets, often in the organics section alongside the quinoa and barley wheat. A recent survey reported that 72 percent of the American public rated coconut oil as a “healthy food”, compared with only 37 percent of nutritionists, while the American Heart Association published a review recommending that people avoid it as much as possible.

Why the disconnect? Is it just a triumph of marketing over science?

“I think there must be some marketers somewhere in the world who are laughing their heads off – a group of people who just decided, ‘let’s sell coconut oil!’” says Rod Jackson, professor of epidemiology at the University of Auckland. Jackson’s been studying heart disease for decades and is an outspoken opponent of saturated fats, including coconut oil.

“It’s interesting that they call it coconut oil rather than coconut fat,” he adds. “It’s solid, so it’s not an oil, it’s a fat.”

The devil is in the reasonably transparent detail on the jar labels — or as Jackson would put it, the jars of coconut fat. What is marketed as coconut oil (which is the term we’ll use here, even if it would be more accurately described as a fat) is around 90 percent saturated fat. This is a higher percentage than that found in butter (about 64 percent) or beef tallow (about 50 percent), and considerably higher than vegetable oils such as canola oil and olive oil (around 7 percent and 14 percent respectively).

And we already know saturated fats are bad for us, right?

Yes, according to decades of research involving thousands of people that have shown saturated fats increase low-density lipoprotein (LDL), or Bad Cholesterol. Countless studies have also shown that increased levels of LDL increases risk of cardiovascular disease, the leading global cause of death, accounting for 17.3 million deaths a year.

It’s true, we all need fat in our diet. But there are the good fats, partly good fats, and fats that are best treated with caution. It’s not very complicated; the more saturated a fat is, the more solid it is, and that’s also the form it’s likely to take on the inside of your arterial walls, causing atherosclerosis.

So are the saturated fats in coconut oil different from other saturated fats?

Coconut oil marketing claims it is largely comprised of medium chain fatty acids (or medium chain triglycerides, or MCTs) rather than long chain or short chain fatty acids. These medium chain fatty acids are said to confer all sorts of health benefits.

However, Jackson says biochemistry can be used to show links between a product and various health outcomes if you go looking for them. But, he warns, consumers should be wary of any health product being sold on biochemical evidence and without the supporting epidemiological evidence – that is, evidence of the benefits of a product in large groups of real living people.

What might make sense at a biochemical level doesn’t necessarily equate with what happens in people. “There are a lot of drugs that have been developed that look promising biochemically but do really bad things to living people.”

What about claims that coconut oil raises Good Cholesterol, or HDL (high-density lipoprotein)?

Coconut oil does seem to raise HDL more than, say, butter. But what does that mean exactly? Not much, says Jackson. There is good evidence that people who naturally have higher HDL have lower risk of heart disease, but this doesn’t establish a causal connection between HDL and heart disease.

Physical activity increases HDL too, so the lower rates of heart disease among people who have higher levels of HDL could be put down to cardiac fitness, rather than the HDL. “HDL is an important predictor of low heart disease risk,” says Jackson, “but when researchers have increased HDL levels with drugs, it has had no effect on the risk of heart disease.”

On the other hand, he explains, “What we do know is that if you eat saturated fats like coconut fat, compared to monounsaturated or polyunsaturated oils like olive oil or canola oil, your LDL will go up. And we know that high levels of LDL increase your risk of heart disease, while lowering LDL reduces the risk of heart disease. This is clear cut.”

But what about those claims that indigenous communities around the world who depend on coconut oil are apparently healthy?

“If you look around the world, where people eat a lot of coconut fat – in Sri Lanka, in southern India, in the Philippines, and the Pacific – they all have high rates of heart disease,” says Jackson. “We might not be able to say their high rates of heart disease are caused by coconut fat alone, but clearly it’s not protecting them from it.”

Finally, is there a difference between coconut milk, coconut cream and coconut oil?

“Coconut milk is a little bit like semi-skimmed milk – it’s just grated coconut flesh and water put through a sieve,” says Jackson. “Coconut cream is a bit like full cream milk – more coconut flesh and less water. Coconut fat is like clarified butter or ghee – it’s the fat extracted from coconut flesh.”

Eaten in moderation, none of them will kill you, not even coconut oil. But they’re all best thought of as a treat, says Jackson, rather than a health product. “Like butter or ice cream, coconut fat is something you can eat occasionally, but not every day.”

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