Coconut Oil and the Boost in HDL “Good” Cholesterol

The effects of coconut oil were compared to butter and tallow. Even if virgin coconut oil and other saturated fats raise LDL “bad” cholesterol, isn’t that countered by the increase in HDL “good” cholesterol?

According to “the experience and wisdom of 200 of the country’s leading experts in cardiovascular diseases,” in a report representing 29 national medical organizations, including the American Heart Association and the American College of Cardiology, we’ve known for nearly half a century that “coconut oil is one of the most potent agents for elevating [blood] serum cholesterol level.” As I discuss in my video Coconut Oil and the Boost in HDL “Good” Cholesterol, studies showing coconut oil elevates cholesterol date back to 1955, when it was first shown experimentally that switching someone from coconut oil to soybean oil could drop cholesterol from around 200 down to 150, as you can see at 0:39 in my video.

Coconut oil can significantly raise cholesterol levels within hours of consumption. In fact, a significant increase in blood cholesterol was found within hours of eating a slice of cake made from either coconut oil (or cod liver oil for that matter), but not from the same cake made from flaxseed oil.

As you can see at 1:10 in my video, coconut oil may even be worse than tallow, or beef fat, but it is not as bad as butter. An interventional trial was published in March 2017: a month-long randomized, controlled, crossover study looking at the impact of two tablespoons per day of virgin coconut oil. The result? Coconut oil elevated cholesterol about 14 percent over the control, which was consistent with seven other interventional trials published to date in a 2016 review.

Hold on. Saturated fats can make HDL, the so-called good cholesterol, go up, so what’s the problem? The problem is that it doesn’t seem to help. Having a high blood HDL level is “no longer regarded as protective.” What? Wait a second. Higher HDL levels are clearly associated with lower risk of heart disease, as you can see at 2:01 in my video. In fact, HDL levels “are among the most consistent and robust predictors of CVD [cardiovascular disease] risk.” Ah, but there are two types of risk factors: causal and non-causal. Association does not mean causation—that is, just because two things are tightly linked, it doesn’t mean one causes the other.

Let me give you an example, which you can see at 2:30 in my video. I bet that the number of ashtrays someone owns is an excellent predictor of lung cancer risk and that study after study would show that link. But, that does not mean that if you intervene and lower the number of ashtrays someone has, their lung cancer risk will drop, because it’s not the ashtrays that are causing the cancer, but the smoking. The ashtrays are just a marker of smoking, an indicator of smoking, as opposed to playing a causal role in the disease. So, just like having a high number of running shoes and gym shorts might predict a lower risk of heart attack, having a high HDL also predicts a lower risk of heart attack. But, raising HDL, just like raising the number of gym shorts, wouldn’t necessarily affect disease risk. How do you differentiate between causal and non-causal risk factors? You put them to the test. The reason we know LDL cholesterol truly is bad is because people who were just born with genetically low LDL cholesterol end up having a low risk of heart disease. And, if you intervene and actively lower people’s LDL through diet or drugs, their heart disease risk drops—but not so with HDL.

People who live their whole lives with high HDL levels don’t appear to have a lower risk of heart attack, and if you give people a drug that increases their HDL, it doesn’t help. That’s why we used to give people high-dose niacin—to raise their HDL. But, it’s “time to face facts.” The “lack of benefit of raising the HDL cholesterol level with the use of niacin…seriously undermine[s] the hypothesis that HDL cholesterol is a causal risk factor.” In simple terms: “High HDL may not protect the heart.” We should concentrate on lowering LDL. So, specifically, as this relates to coconut oil, the increase in HDL “is of uncertain clinical relevance,” but the increase in LDL you get from eating coconut oil “would be expected to have an adverse effect” on atherosclerotic cardiovascular disease risk.

But, what about the MCTs, the medium-chain triglycerides? Proponents of coconut oil, who lament “that ‘coconut oil causes heart disease’ has created this bad image of [their] national exports,” assert that the medium-chain triglycerides, the shorter saturated fats found in coconut oil, aren’t as bad as the longer-chain saturated fats in meat and dairy. And, what about that study that purported to show low rates of heart disease among Pacific Islanders who ate large amounts of coconuts? I cover both of those topics in my video What About Coconuts, Coconut Milk, and Coconut Oil MCTs?.


I love topics that give me an excuse to talk about scientific concepts more generally, like various study designs in my video Prostate Cancer and Organic Milk vs. Almond Milk or my discussion of direct versus indirect risk factors in this one.

How do we know LDL is bad? Check out How Do We Know That Cholesterol Causes Heart Disease?.

But, wait. Isn’t the whole saturated fat thing bunk? No. See:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

What About Coconuts, Coconut Milk, and Coconut Oil MCTs?

Do the medium-chain triglycerides in coconut oil and the fiber in flaked coconut counteract the negative effects on cholesterol and artery function?

Studies of populations who eat a lot of coconuts are “frequently cited” by those who sell coconut oil “as evidence that coconut oil does not have negative effects on cardiovascular health.” For example, there was an apparent absence of stroke and heart disease on the island of Kativa in Papua New Guinea. What were they eating? Their diets centered around tubers, like sweet potatoes, with fruits, greens, nuts, corn, and beans. Although they ate fish a few times a week, they were eating a largely whole food plant-based diet. It’s no wonder they may have had such low rates of artery disease. And, one of the whole foods they were eating was coconut, not coconut oil.

Now, if you go to Pukapuka, even more coconuts are eaten. In fact, as you can see at 0:51 in my video What About Coconuts, Coconut Milk, and Coconut Oil MCTs?, there’s even an island where coconuts make up most of what people eat—and they do get high cholesterol. How can a population eating 87 percent plant-based, with no dairy and only rare consumption of red meat, chicken, and eggs, have cholesterol levels over 200? Well, they’re eating all those coconuts every day. What are their disease rates like? We don’t know. There are no clinical surveys, no epidemiological death data, and no autopsies. Some EKGs were taken, which can sometimes pick up evidence of past heart attacks, but they found few abnormalities. The sample was too small to be a definitive study, though. And, even if they did have low disease rates, they weren’t eating coconut oil—they were eating coconut in its whole form.

Coconut oil proponents pointing to these studies is like the high fructose corn syrup lobby pointing to studies of healthy populations who eat corn on the cob or the sugar industry pointing to studies on fruit consumption and saying you can eat all the refined sugar you want. But fruit has fiber and so do coconuts. Just as adding psyllium fiber (Metamucil) to coconut oil can help blunt the adverse effects on cholesterol, fiber derived from defatted coconut itself can reduce cholesterol levels as much as oat bran. What’s more, the plant protein in coconuts, which is also missing from the oil, may help explain why whole coconuts may not have the same effects on cholesterol. Although coconut fat in the form of powdered coconut milk may not have the same effects on cholesterol as coconut oil, frequent consumption, defined as three or more times a week, has been associated with increased risk of vascular disease, stroke, and heart disease. And, no wonder, as coconut milk may acutely impair artery function as badly as a sausage and egg McMuffin.

Researchers tested three different meals including a Western high-fat meal that “consisted of an Egg McMuffin®, Sausage McMuffin®, 2 hash brown patties and a non-caffeinated beverage (McDonald’s Corporation)” a local high-fat meal, and an “isocaloric low-fat meal.” The study was conducted in Singapore, so the more traditional local high-fat meal was rice cooked in coconut milk and served with anchovies and an egg. These two different high-fat meals were put up against the same amount of calories in an unhealthy low-fat meal of Frosted Flakes, skim milk, and juice. At 3:21 in my video, you can see the artery function—that is, its ability to relax normally—before and after eating each of the three meals. Researchers found that artery function is significantly crippled within hours of consuming the McMuffins and also the local high-fat meal with coconut milk. So, whether the fat is mostly from meat and oil or from coconut milk, the arteries clamped down similarly, whereas that horrible sugary breakfast had no bad effect on artery function. Why? Because as terrible as the Frosted Flakes meal was, it had no saturated fat at all. (It also didn’t have contain any eggs, so that might have helped, too.)

Coconut oil proponents also try to argue that coconut oil has MCTs, medium-chain triglycerides, which are shorter-chain saturated fats that aren’t as bad as the longer-chain saturated fats in meat and dairy. You can’t apply the MCT research to coconut oil, though. Why not? Well, MCT oil is composed of MCTs—about 50 percent of the medium-chain fat caprylic acid and the other 50 percent of the MCT capric acid—whereas those MCTs make up only about 10 percent of coconut oil. Most of coconut oil is the cholesterol-raising, longer-chain saturated fats, lauric and myristic. “It is therefore inaccurate to consider coconut oil to contain either predominantly medium-chain fatty acids or predominantly medium-chain triglycerides. Thus, the evidence on medium-chain triglycerides cannot be extrapolated to coconut oil.”

It’s actually quite “a common misconception” that the saturated fat in coconut oil is comprised of mainly MCTs. Actually, as we discussed, coconut oil is mainly lauric and myristic, both of which have potent bad LDL cholesterol-raising effects. “Coconut oil should therefore not be advised for people who should or want to reduce their risk of CHD,” coronary heart disease, which is the number-one killer of U.S. men and women. The beef industry, for example, loves to argue that beef fat contains stearic acid, a type of saturated fat that doesn’t raise cholesterol. Yes, but it also has palmitic and myristic acids that, like lauric acid, do raise cholesterol, as you can see at 5:12 in my video.

If you compare the effects of different saturated fats, as you can see at 5:29 in my video, stearic acid does have a neutral effect on LDL, but palmitic, myristic, and lauric acids shoot it up—and, frankly, so may MCT oil itself, as it bumps up LDL 15 percent compared to control. Bottom line? “Popular belief”—spread by the coconut oil industry—“holds that coconut oil is healthy, a notion not supported by scientific data.” The science just doesn’t support it.

So, basically, “coconut oil should be viewed no differently” from animal sources of dietary saturated fat. A recent review published in the Journal of the American College of Cardiology put it even more simply in its recommendations for patients. When it comes to coconut oil, “avoid.”

Okay, but doesn’t saturated fat boost HDL, the so-called good cholesterol? Check out Coconut Oil and the Boost in HDL “Good” Cholesterol.


Isn’t coconut oil supposed to be good for Alzheimer’s, though? See my video Does Coconut Oil Cure Alzheimer’s?

If you want to learn more about the original McMuffin artery studies, see The Leaky Gut Theory of Why Animal Products Cause Inflammation.

You may also be interested in Flashback Friday: Coconut Oil and Abdominal Fat.

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

Arsenic in Rice Milk, Rice Krispies, and Brown Rice Syrup

I recommend people switch away from using rice milk

For kids and teens, the amount of arsenic flowing through their bodies was found to be about 15 percent higher for each quarter cup of rice consumed per day, and a similar link was found in adults. A study of pregnant women found that consuming about a half cup of cooked rice per day could raise urine arsenic levels as much as drinking a liter of arsenic-contaminated water at the current upper federal safety limit. These findings “suggest that many people in the United States may be exposed to potentially harmful levels of arsenic through rice consumption.” which I explore in my video Arsenic in Rice Milk, Rice Krispies, and Brown Rice Syrup.

Do you know where Americans get most of their rice arsenic? From Rice Krispies, though brown rice crisps cereal may have twice as much, as I discuss in my video Arsenic in Rice Milk, Rice Krispies, and Brown Rice Syrup.

“Organic brown rice syrup (OBRS) is used as a sweetener in organic food products as an alternative to high-fructose corn syrup.” Big mistake, as organic brown rice syrup products “may introduce significant concentrations” of toxic arsenic into people’s diets. For example, two energy chews sweetened with brown rice syrup might hit the provisional upper daily arsenic intake based on the water standards.

“Toddler formulas with added organic brown rice syrup have 20 times higher levels of inorganic [toxic] arsenic than regular formulas,” and in older children, thanks to brown rice syrup, a few cereal bars a day “could pose a very high cancer risk.”

What about rice milk? A consensus statement of both the European and North American societies for pediatric nutrition recommends the “avoidance of rice drinks for infants and young children,” and, generally, toxic “inorganic arsenic intake in infancy and childhood should be as low as possible.”

To this end, the United Kingdom has banned the consumption of rice milk for young children, a notion with which Consumer Reports concurred, recommending no servings a week of rice milk for children and no more than half a cup a day for adults, as you can see at 1:56 in my video.

The arsenic in various brands of rice milk ranges wildly—in fact, there’s a 15-fold difference between the highest and lowest contamination, suggesting manufacturers could make low arsenic rice milk if they wanted. As you can see at 2:16 in my video, Consumer Reports found rice drinks from Pacific and Rice Dream brands were right about average, though, for Rice Dream, it appears the vanilla or chocolate flavors may be lower. It doesn’t seem we have anything to worry about with rice vinegar, but rice pasta and rice cakes end up similar to pure rice in terms of arsenic levels, which makes sense because that’s pretty much what they are—pure rice. However, pasta is boiled, so we’d expect the levels to be cut 40 to 60 percent, like when you boil and drain rice.

If you just couldn’t live without rice milk for some reason, you could make your own using lower arsenic rice, like brown basmati from India, Pakistan, or California, but then your homemade rice milk might have even less nutrition, as most of the commercial brands are at least fortified. Better options might be soy, oat, hemp, or almond milk, though you don’t want kids to be drinking too much almond milk. There have been a few case reports of little kids drinking four cups a day and running into kidney stone problems due to its relatively high oxalate content, which averages about five times more than soy milk. More on oxalates in my video series starting with Oxalates in Spinach and Kidney Stones: Should We Be Concerned?

I have about 40 videos that touch on soy milk, discussing such topics as how it may normalize development in girls and reduce breast cancer risk, as well reduce prostate cancer risk in men. Some of the latest science on soy milk includes an association with better knee x-rays, suggesting protection from osteoarthritis, and an interventional study suggesting improved gut health by boosting the growth of good bacteria. However, drinking 3 quarts a day, which is 10 to 12 daily cups, for a year may inflame your liver, but two cups a day can have an extraordinary effect on your cholesterol, causing a whopping 25 percent drop in bad cholesterol after just 21 days.

An ounce and a half of almonds, about a handful, each day, can drop LDL cholesterol 13 percent in six weeks and reduce abdominal fat, though a cup of almond milk only contains about ten almonds, which is less than a third of what was used in the study. So, it’s not clear if almond milk helps much, but there was a study on oat milk compared to rice milk. As you can see at 4:37 in my video, five weeks of oat milk lowered bad cholesterol, whereas rice milk didn’t, and even increased triglycerides and may bump blood pressure a bit. However, the oat milk only dropped LDL about 5 percent and that was with three cups a day. As plant-based alternatives go, it appears soy milk wins the day.

So, why drink rice milk at all when there are such better options? There really isn’t much nutrition in rice milk. In fact, there are case reports of severe malnutrition in toddlers whose diets were centered around rice milk due to multiple food allergies. Infants and toddlers have increased protein requirements compared to adults, so if the bulk of a child’s diet is rice milk, coconut milk, potato milk, or almond milk, they may not get enough, as you can see at 5:23 in my video. In fact, cases of kwashiorkor—that bloated-belly protein- and calorie-deficient state of malnutrition—due to rice milk have been reported in Ethiopia…and Atlanta, Georgia, because literally 99 percent of the child’s diet was rice milk. So, these malnutrition cases were not because they drank rice milk, but rather because they drank rice milk nearly exclusively. I just use these examples to illustrate the relative lack of nutrition in rice milk. If you’re going to choose a milk alternative, you might as well go for one that has less arsenic—and more nutrition.

I have released several videos on soy milk, but only one on almond milk video so far: Prostate Cancer and Organic Milk vs. Almond Milk. I plan on producing many more on choosing between various milk options, so stay tuned.


If you’ve missed any of the useful material on dietary arsenic I’ve also shared, please see:

The final four videos in this series take all of this information and try to distill it into practical recommendations:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations: