Coconut oil is touted for its nutritional value, with some even suggesting that it could help reverse dementia. Let's take a nice, refreshing look at the science.
Like Kanye West, coconut oil has recently undergone a 180° change in its public perception. Coconut oil is a saturated fat meaning that it is solid at room temperature. While this isn’t a problem in the kitchen or the pantry, it may lead to plaques and narrowed blood vessels in the body. In the 1950s, prominent nutritionists began opposing saturated fats. The studies from that era suggested these fats increased cholesterol levels, leading to heart disease. Coconut oil is more than 90 percent saturated fat, so it was considered the less healthy option. Unsaturated fats like vegetable or soybean oil — which are less likely to clog arteries — were preferred instead.
As nutritional science evolved, researchers discovered there were two types of cholesterol. Saturated fats raised the levels of the good kind of cholesterol — high-density lipoprotein (HDL). Based on this new information, coconut oil was re-discovered by health and wellness companies.
Many people believe that coconut oil is a panacea for many maladies, including Alzheimer’s disease and dementia. However, coconut oil is just another food — one with benefits and drawbacks. There isn’t any viable scientific evidence that it prevents, reverses, or treats Alzheimer’s or dementia at any stage of the disease. OK, so, where did this wild claim come from? And is there any basis to it whatsoever?
What’s behind the claim that coconut oil can reverse dementia? It has to do with the ketone diet
Coconut oil’s link to the brain isn’t completely imaginary: The link is the ketogenesis process — a process in which our bodies use fats as fuel, instead of sugars. The keto diet cuts out sugar, forcing the body to turn to fat, and burn it off.
Eating coconut oil increases the levels of fat fuel sources called ketone bodies in the blood. And that’s where this dementia and Alzheimer’s theory enters the picture: There is ongoing research to better understand whether ketone bodies — and diets like the ketone diet — can help protect brain health, and stave off neurodegenerative diseases like Alzheimer’s and other forms of dementia. That research is still underway and so far inconclusive.
The important thing to know for now is that eating coconut oil, alone, will not flip the metabolic switch and enact the process of ketogenesis. In fact, if you’re looking to design a keto diet, coconut oil may not even be the best choice of oil out there.
What scientific studies actually say about coconut oil, MCTs and brain health
Proving that coconut oil prevents dementia isn’t an easy task. Despite several decades of research, there are only two approved treatments for the early stages of Alzheimer’s. While the drugs may slow the disease early on, there isn’t any surefire way to prevent or reverse Alzheimer’s disease and dementia.
“It’s unfortunate that coconut oil has been given this health halo,” researcher Marie-Pierre St-Onge told Marketplace. “Especially since we know that saturated fats increase cholesterol concentrations, which increases your risk of cardiovascular disease.”
For the past 20 years, St-Onge has been researching solutions to the obesity epidemic. One key finding: a specific kind of saturated fat known as medium chain triglycerides (MCTs), the “good fats found in coconut oil, might help people struggling with obesity to lose weight. There have been three MCT studies so far that have tested whether MCTs managed to reduce cognitive impairment in Alzheimer’s, compared to a placebo. Across the board, these studies found that the participants who received MCT didn’t perform any better in the cognitive tests than people who received the placebo.
Even if there were hundreds of studies on coconut oil, linking diet to brain health is complicated: It is very unlikely that any individual food, or most diets for that matter, can actually prevent Alzheimer’s or dementia. Take for example the Mediterranean and MIND-style diets. To date, they provide the most compelling evidence that food may reduce the risk of developing Alzheimer’s disease or dementia. But the researchers involved in these studies are quick to point out the link is still not proven. The trouble is that tracking what people eat and accounting for other health-related factors like socioeconomic status is very hard.
One thing scientists do know about these diets: Eating healthier food can help lower cholesterol levels and address diabetes, among other health benefits. So, at the very least, health diets are shown to improve some aspects of health — and these two aforementioned aspects are known to influence the risk of developing Alzheimer’s and other forms of dementia.
Is coconut oil good for you?
So, is “coconut oil” healthy? Not by most measures. This food is made up almost entirely of saturated fat. When you eat a tablespoon of coconut oil, 13 out of those 14 grams will be saturated fat — nearly double the amount of saturated fat found in the same volume of butter, two and a half times more than lard, and over six times more saturated fat than you’ll find in olive oil.
In fact, Costco’s Kirkland brand of coconut oil is at the center of a class-action lawsuit for false claims that it is “healthy.”
In 2020, the American Heart Association reviewed all the studies involving coconut oil. The researchers found that while coconut oil increases HDL cholesterol, it also increases the levels of bad low-density lipoprotein (LDL) cholesterol. In the end, the association concluded that unsaturated fats are a healthier option.
“Advertisements give the impression that purportedly beneficial constituents other than saturated fat compensate for its adverse effects on LDL cholesterol,” the American Heart Association researchers wrote. “Yet, controlled trials in humans are not available that support beneficial actions of the components of coconut oil on cardiovascular disease risk factors or mechanisms.”
Coconut oil as a nutritional supplement
Nutritional supplements like coconut oil and MCT oil are also loosely regulated. That means the label could be inaccurate, or the product could contain undeclared or illicit ingredients. Pieter Cohen, a physician and researcher at Cambridge Health Alliance regularly speaks with patients considering natural supplements and vitamins. “Sometimes people use these hoping to receive the benefits of something more wholesome and natural,” he said. “At other times, consumers are drawn to them because they are worried about side effects from pharmaceutical drugs.” Unfortunately, however, he and other experts say natural supplements and vitamins haven’t proven their effectiveness in studies of brain health, memory, Alzheimer’s disease, or dementia. Due to the lax regulation in the supplement industry, they may actually cause harm to patients instead of helping them.
The bottom line: While a single tablespoon of coconut oil here and there is unlikely to cause any long-term harm, eating lots of coconut oil probably isn’t healthy. And when it comes to the claim of its ability to boost brain health and even reverse Alzheimer’s or dementia, there is no proof at all.