What’s Best for Eczema (Atopic Dermatitis): Coconut Oil vs. Mineral Oil vs. Vaseline

Natural topical remedies for eczema, including licorice root gel, St. John’s Wort cream, and emollients such as coconut oil, mineral oil, and petroleum jelly, are put to the test.

Despite the availability of drugs with proven efficacy for eczema, like topical steroids, many patients seek out natural alternatives. Which plant, then, should be used for which skin disease? In the case of eczema, two appeared to beat out placebo. One was licorice root. As you can see at 0:24 in my video Eczema Treatment with Coconut Oil vs. Mineral Oil vs. Vaseline, smearing on a placebo gel didn’t appear to help much with clearing redness or itchiness after one week or two weeks, but a 1 percent licorice gel and especially a 2 percent gel did seem to clear the symptoms in most patients. The researchers concluded that licorice extracts could be considered an effective eczema treatment agent.

The other successful trial was with a St. John’s wort cream, showing a reduction in eczema severity scores week by week superior to that of placebo, as you can see at 0:49 in my video. So, it works better than nothing, but does it work better than drugs? Better than the topical steroids? That we don’t know. Sometimes, the drugs don’t work on so-called recalcitrant atopic dermatitis, so researchers in Japan asked patients to drink four cups of oolong tea every day for a month. Most patients “showed marked to moderate improvement,” starting after one or two weeks, and then most remained better even five months after they stopped. The problem is there was no control group, so we don’t know how many would have gotten better on their own. But, since drinking tea is healthy anyway, why not give it a try? 

Let’s get back to topical treatments. As you can see at 1:43 in my video, a vitamin B12 cream showed better results than the same cream without vitamin B12. Most of the patients and doctors rated the results of the B12 cream as “good,” which was better than they scored the placebo cream. 

Regardless of what topical agent you use, steroid or otherwise, “first and foremost, it is essential that the skin barrier is protected and maintained with the use of emollients,” meaning moisturizers, ideally once or twice a day, especially right after showering, to lock in the moisture. Petroleum jelly, like Vaseline, is highly effective, but it “is greasy and can be messy,” so what about something like coconut oil, which is less greasy? It was found to improve skin dryness, though no better than mineral oil, which is cheaper. Is mineral oil safe, though?

Exposure to mineral oil was found to be associated with rheumatoid arthritis, but that was occupational exposure to industrial mineral oils, like hydraulic fluid. The same group of researchers subsequently found that cosmetic grade mineral oil did not seem to carry the same risk. In general, topically applied mineral oil shouldn’t present any health risk, but that doesn’t mean…you can safely inject it into your penis, as that “may have devastating cosmetic and sexual function consequences.” There is, however, evidently one good use for mineral oil on the penis, and that’s for “penile zipper entrapment.” Skin of the penis “is susceptible to entrapment in the zipper of careless young boys, particularly those who fail to wear undergarments. Understandably, this mishap provokes distress in the unfortunate victim, in his parents, and ultimately in the health care provider charged with the task of liberating the organ.” A recommended textbook approach is surgery, believe it or not, but if you simply dose liberally with some mineral oil, you can just slip the zipper off and “physical and psychologic trauma is minimized for all parties involved…”

But, just because mineral oil works as well as coconut oil for dry skin, doesn’t mean it works as well for eczema. Head-to-head topical virgin coconut oil works better than topical mineral oil at decreasing eczema severity, with twice as many children experiencing an excellent response after two months treatment. Thus, among pediatric patients with mild to moderate eczema, topical application of virgin coconut oil was superior to mineral oil, but what about compared to virgin olive oil? As you can see at 4:19 in my video, olive oil worked, dropping eczema severity, but coconut oil worked better. 

As I discussed previously in my video What about Coconuts, Coconut Milk, and Coconut Oil MCTs?, we know that coconut oil has a lot of saturated fat, so we don’t want to consume it, but the saturated fat isn’t absorbed into your skin unless you are a baby, when your skin is so thin that you can actually absorb saturated coconut fat into your bloodstream. But, in older children and adults, using coconut oil on your skin or hair is considered safe. 

What about treating eczema with just plain Vaseline? People with eczema already know it can be expensive to deal with. The average out-of-pocket costs can be $274 a month, which is more than a third of a typical family’s disposable income. In contrast, you can rub a kid from head to toe with petroleum jelly for about four cents, whereas coconut oil or some of the fancier over-the-counter moisturizers can be many times more expensive, though not as bad as some prescription moisturizers that can cost more than a hundred dollars per tube and work no better than the over-the-counter stuff, as you can see at 5:50 in my video. There is simply no evidence “prescription device moisturizers” are superior to the traditional, petroleum jelly-based over-the-counter products that can be 65 times cheaper.

Doesn’t virgin coconut oil have active ingredients, though, whereas petroleum jelly is just inert? Vaseline has been around since 1872, but it took the scientific community 144 years to put it to the test. We now know it isn’t inert at all, significantly upregulating genes that fight infection, inducing the expression of genes that help with barrier function, increasing the thickness of the protective outer layer of skin, and actively reducing inflammation. Yes, but is it safe? Not… if you inject it into your penis. (What is it with men injecting stuff into their penis?!) “In the less severe cases, the problem [this self-injection creates] could be solved by basic surgery. Otherwise, it may require major reconstruction. Evidently, “Vaseline self-injection of the penis” is done a lot by prisoners, giving a whole new meaning to the term “Jailhouse Rock.” An unbelievable one in six inmates at the largest prison in Hungary admitted to “Vaseline self-injection.” Or how about actual rocks, the surgical implantation of stones in the penis, which has also been reported? What about injecting industrial silicone? (I will never look at silicone caulk the same way ever again.) When men were asked why they were injecting cod liver oil, a fishy substance, into their penises, most explained it was because they felt underendowed, as you can see at 7:40 in my video, but one guy said he “just want[ed] to try.” Um…okay. Why inject cod liver oil into your penis, though, when you can just inject the mercury directly and cut out the middlefish?

Back to eczema! Based on 77 studies of moisturizers for eczema, researchers “did not find reliable evidence that one moisturizer is better than another,” though a consensus of experts concluded that petroleum jelly may be best for skin barrier function protection.

What about eating coconut oil? See Coconut Oil and the Boost in HDL “Good” Cholesterol and What About Coconuts, Coconut Milk, and Coconut Oil MCTs?.

What about the swallowing oil supplements? That was the topic of my video, Eczema Treatment with Evening Primrose Oil vs. Borage Oil vs. Hempseed Oil.

I have more on eczema coming up, so make sure you’re subscribed so you don’t miss anything.

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:

Dietary Supplements for Eczema (Atopic Dermatitis)

Are there dietary supplements that can help with atopic dermatitis?

Atopic dermatitis, more commonly known as eczema, ranks “as the skin disease with the greatest health burden worldwide” because it’s just so common, affecting maybe one in ten kids and about 3 percent of adults, causing patches of red, itchy skin. Topical steroids, like cortisone cream, have been “the mainstay treatment” since their Nobel Prize-winning discovery in 1950.

People are scared of steroids, though, and “it is not uncommon for patients to express irrational fear and anxiety about using topical corticosteroids”—steroid creams and ointments. This phobia may arise from confusing topical steroids with oral or injected steroids, which have different effects. Really potent topical steroids can thin your skin, but skin thickness should return to normal a month after stopping. So, yes, topical steroids can cause side effects, but the concern people have “seems out of proportion” to the small risk they actually pose. Still, if there’s a way you can resolve a problem without drugs, that’s generally preferable. What did they do for eczema before the 1950s?

In the 1930s, some researchers tried using vitamin D dissolved in corn oil, and to their surprise, it worked—but so did the corn oil without the vitamin D they were using as a control. Others reported cases improving after feeding flaxseed oil and even ingesting lard, from a study “aided by a grant from the National Live Stock and Meat Board,” which apparently did not want to be left out of the action. The problem is that none of these studies had a control group. So, yes, after feeding someone corn oil for 12 to 18 months, they got better—but maybe they would have gotten better anyway. You don’t know until you put it to the test. 

Nearly all of those researchers who claimed benefit from the use of the various fats apparently “lack[ed]…any great interest in a controlled series,” but one researcher tested some oils and found no evidence of benefit over routine treatment. Indeed, as you can see at 2:06 in my video Eczema Treatment with Evening Primrose Oil vs. Borage Oil vs. Hempseed Oil, most got better either way, which suggests that the previous “benefits claimed may be due to the usual treatment, with perhaps a dash of enthusiasm.”

By then, hydrocortisone was out, so the medical community gave up on dietary approaches—until a letter was published in 1981 about the treatment of eczema with supplements of evening primrose oil, which contains gamma linolenic acid, an anti-inflammatory omega-6. And, indeed, when it was put to the test, it seemed to help, but then a subsequent larger study found no effect. Whenever there are conflicting findings, it helps to do a meta-analysis, where you put all the studies together. So, there was the study that showed benefit, the one that didn’t, and seven other studies. What did those find? Seven out of the seven showed benefit. “The results show that the effects of Epogam [a brand of primrose oil supplement] are almost always significantly better than those of placebo.” Case closed, right? Well, the analysis was funded by the supplement company itself, which can be a red flag, and where exactly were the other seven studies published? They weren’t. The company just said it did those seven studies but never released them. When asked to hand them over, the company said it would but never did, even threatening a lawsuit against researchers who dared to question the studies’ efficacy.

An independent review failed to find evidence that evening primrose oil or borage oil worked better than placebo. “As we bid goodnight to the evening primrose oil story, perhaps we can awaken to a world where all clinical trial data…reach the light of day…” 

Borage oil actually has twice the gamma linolenic acid as evening primrose yet it still didn’t work, but that didn’t stop researchers from trying hempseed oil, which “has been used as a food and medicine for at least 3000 years in China.” Researchers tried giving about a quarter cup of hempseeds’ worth of oil to people every day for a few months and found significant improvements in skin dryness, itchiness, and the need for medications—but not compared to placebo. In fact, studies of dietary supplements across the board, whether fish oil, zinc, selenium, vitamins D, E, or B6, sea buckthorn oil, hempseed oil, or sunflower oil, overall, showed “no convincing evidence that taking supplements improved the eczema of those involved.” That’s disappointing, but wait a second. That’s just for oral supplements. What about natural remedies applied topically? I discuss that in my video Eczema Treatment with Coconut Oil vs. Mineral Oil, vs. Vaseline.

Meta-analyses can be skewed the other way, too, when negative results are quietly shelved so only positive findings are published. Antidepressant medications are a classic example of this publication bias. Check out my coverage of it in my video Do Antidepressant Drugs Really Work?.

As I queued up at the end, I cover topical natural treatments in my next video, Eczema Treatment with Coconut Oil vs. Mineral Oil vs. Vaseline.

What about skipping the lard and trying to eat more healthfully? See what happened in Treating Asthma and Eczema with Plant-Based Diets.


For more on skin health, check out:

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:

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: