Study Shows Chocolate May Cause Acne

Study Shows Chocolate May Cause Acne

Chocolate has a long history in the acne diet debate. It was subject of the first study that created the ‘diet doesn’t affect acne’ myth. Before that dermatologists frequently prescribed chocolate restriction to acne patients. Now, a small study claiming drastic increase in acne after eating chocolate fuels the controversy.

So could it be? Could chocolate really cause acne? In this post we’ll look at the science behind these questions and hopefully get to the bottom of this.

Massive increase in acne after eating chocolate?

WedMD in 2011 reports about a small, unpublished study where 10 young men with acne were allowed to eat as much pure chocolate as they wanted, up to a maximum of 3 4-ounce candy bars. The candy bars were pure chocolate, made of 100% cocoa. Before the study they the men had an average of 3 pimples. By 4th day after eating chocolate that figure had jumped to 13. And after a week the men had an average of 18 pimples.

Going from 3 to 18 pimples is dramatic. In fact it’s so dramatic I’m quite skeptical. These results don’t line up with real world reports by acne patients. If chocolate would have such a dramatic impact on acne, forums would be buzzing about this. But stories of chocolate aggravating acne are quite rare in acne forums.

The researchers say they are planning a larger, follow up study, but so far there’s nothing in the published literature.

Prior to this study the only evidence we had were the 2 poor quality studies that started the diet doesn’t cause acne myth. They showed no effect from chocolate, but both studies have been criticized widely and we can’t really draw firm conclusions from them.

The bottom line is that we just don’t know at this point. Most of the available research shows chocolate doesn’t cause acne, but that research is low quality and we can’t draw firm conclusions based on it.

At this point I wouldn’t be too worried about chocolate, but I wouldn’t completely dismiss the possibility. The book Chocolate in Health and Nutrition has a brief chapter on acne. One of the points they make is that chocolate has biologically active substances that may affect acne, such as caffeine.

Chocolate also has somewhat mixed relationship with insulin.

Chocolate and insulin levels

Insulin is one of the key factors in hormonal acne. High insulin levels drive all the other hormones behind acne, and reducing insulin levels is one of the best ways to treat hormonal acne. Chocolate has somewhat of a mixed effect on insulin levels. Chocolate can spike insulin levels after a meal, but it can also reduce insulin resistance and have a longer term positive effect.

Chocolate spikes insulin levels

So how could pure chocolate cause acne? A study published in the Journal of Nutrition in 2003 gives some clues, namely that chocolate can spike insulin levels.

In this study they bought several pairs of food from supermarket, including breakfast cereals, cakes, flavored milk, ice cream, pudding and chocolate bars. For each pair they chose a food flavored with chocolate (cocoa powder) and another food flavored with something else. For example, in the flavored milk category one food was chocolate milk and another was strawberry milk. Aside from flavoring the foods within a pair were very similar. They had similar calorie, sugar, carbohydrate, protein and fat content.

They then fed the foods to the 10 participants. They were interested in difference in blood sugar and insulin responses to the foods within a pair. Let’s say Mary was one of the participants. So the researchers gave Mary chocolate milk one day and strawberry milk in another day, and then compared the how her blood sugar and insulin levels responded.

What they found was pretty interesting. As you would expect, with similar calorie and carbohydrate content both foods triggered similar increase in blood sugar levels.

But the effect on insulin levels was where this gets interesting. Across all the foods and participants the food flavored with chocolate increased insulin levels 28% (mean value) more than the food with an alternative flavoring. The difference was even bigger for flavored milks where chocolate milk increased insulin levels 45% more than strawberry milk.

The researchers couldn’t say what it was in chocolate that caused this excessive insulin response, but it’s probably some of the amino-acids.

But chocolate improves insulin resistance

And just that I thought I found a clever explanation for chocolate causing acne, science blows over my shaky card-house.

There’s quite a bit of research interest in cocoa as a way to prevent and protect against heart disease. Those studies have shown chocolate can reduce insulin resistance. In one study the participants were given 100g of either flavonoid-rich dark chocolate or white chocolate (presumed to be flavonoid free) for 15 days. After 15 days their blood sugar levels and insulin resistance were measured using the oral glucose tolerance test – basically you drink a glass of sugar water and your blood sugar and insulin levels are measured several times over the next 2 hours.

Compared to baseline (pre-study) measurements, dark chocolate reduced blood sugar levels by about 20% and insulin levels by almost 40%. White chocolate had a slight negative effect on blood sugar and insulin levels. Other studies have also shown positive effects.

But please don’t go running into supermarket to get your dark chocolate fix quite yet. This was not a blinded study. And if the history of science is clear on something, it’s on the fact that open-label (unblinded) studies produce overtly optimistic results. I can say with confidence that cocoa will not be a miracle cure for diabetes or insulin resistance.

So while we should take these results with a grain of salt, we shouldn’t dismiss them. Cocoa is rich in antioxidants and flavonoids, and studies on other flavonoid-rich foods have also shown improvements in insulin resistance. So it’s certainly plausible that cocoa reduces insulin resistance.

Making sense of chocolate and insulin

This love-hate relationship chocolate has with insulin may seem quite confusing. But we are really talking about 2 different things here. Post-meal insulin response and long-term insulin levels are different beasts. It’s possible that something in chocolate triggers a fairly high post-meal insulin response, but at the same time the antioxidants in chocolate improve overall insulin levels.

Of course there are other ways to get these antioxidants. I’ve written lot about antioxidant potential of green tea and two posts about how to boost it: here and here.

If you want to try your luck with chocolate, do remember to go for dark chocolate with little to no added sugar. Don’t fool yourself thinking that any old chocolate bar will be ‘good for your insulin levels and acne’.


So does chocolate cause acne or not? At this point I would say probably not. The best studies available show no relationship between chocolate and acne. The one unpublished study showing dramatic increase in acne after eating chocolate doesn’t line up with real world results. If chocolate would have such a negative effect on acne we would see it talked in every acne forum. But so far the stories of chocolate causing acne are fairly rare.

It’s not totally implausible thought. Chocolate can increase insulin levels. Some people may have an allergic reaction to chocolate that shows up on the skin. Finally, some people may react negatively to caffeine or other bioactive substances in cocoa. But I would say these cases are the minority and there’s no reason to ditch the pleasure of occasionally indulging with dark chocolate.

About Me

Hi, I am Acne Einstein(a.k.a. Seppo Puusa). I'm a bit of a science nerd who is also passionate about health. I enjoy digging through medical journals for acne treatment gems I can share here. You can read more about my journey through acne and how I eventually ended up creating this.

13 thoughts on “Study Shows Chocolate May Cause Acne”

  1. Hi. I just posted on the acne.or board that chocolate does definitely make me break out. I’m 50 (!) now and had suffered for years with acne, but when I changed my diet (detox from candida, now eating a reasonable amount of carbs) AND stopped using cleansers, just water and a towel to dry/gently exfoliate, my acne virtually disappeared. It seems I have to maintain the dual regimen, above, to keep the acne away. However, I have learned–through experimentation–that there is still one trigger that can make me develop golf-ball cysts on my chin and jawline, and that food is chocolate. Not a couple of small squares, but a big candy bar, which measures about 4″ x 6″. That amount of chocolate eaten over the course of one day will generate acne 48 hours later, guaranteed. I think it may be the methyl bromide used by the chocolate manufacturers that is the irritant. The interaction between bromide and iodide in the body has been noted to create cysts and pustules.

    • Thanks for sharing your experience Kimmie. It’s always nice to hear from real people instead of just reading academic studies 🙂

      Is it possible you are allergic to chocolate? That could be another possible explanation as to why it makes you breakout.

    • My skin has been quite clear for years but at age six oh, chocolate is the one thing that will almost invariably result in a pimple. Although I love it, I am writing chocolate off forever!

  2. Hi, I have acne problems and after consuming chocolates, I had really bad outbreak the following day. Tried many times and the result is always bad.

  3. My best friend and I must have the same setup inside. We are both allergic to chocolate. I used to eat chocolate everyday as a kid, and well into adulthood. Until about 6 years ago, when we decided to do our own personal study. I always had acne,always. It would range from the typical teenage white and black heads to the chocolate ones that seemed more like hard cyst that never came to a head, and was very deep and very sore. There was barely an itch. And those suckers took weeks to go away, and they would always come back in the same spots, with no hopes of coming to a head. My skin has been smooth and clear since my body got rid of all the cocoa ( I do very rarely get a small pimple around my monthly, but its always gone the next day.) I do sometimes eat fried foods, dairy,sweets (just not many sweets) my fruits and veggies, no pork, i only chicken turkey ,seafood’s,and sometimes red meat. I sometimes drink alcohol, No breakouts…..When i read food labels, I specifically look for cocoa in any form shape or color. If its in there,its a no go. If something I would like to eat is even packaged in the same wrapper as cocoa, its a no go. if by some accident I get a hold of cocoa, ( I work in fast food and have to make chocolate milkshakes) I notice I break out. I leave it be, put some aloe vera on it, and it will eventually go away. Chocolate freaks me out, my best friend not so much. She is braver than I. It does make me laugh however when I read folks saying there is no link in cocoa and acne. I understand its not really talked about in forums, but to be honest, this is time I have even been on the computer in a long time. I am hoping one day when I am in my 50’s or 60’s to just say whatever, and go all out with a massive chocolate party. Id say well deserved after going from a severe chocoholic to, afraid to even eat it in my dreams (nightmare),(I’m a nightly dreamer) individual. To all those who know there is a link, good luck in your journeys with chocolate. I know the battle,it is very hard. But eventually we will overcome. Peace to all.. 🙂

    • As I mentioned in the post, the relationship between chocolate and acne is complicated and mixed. It’s possible chocolate causes acne, but there’s no good evidence to show that. I personally don’t think chocolate affects acne that much, individual exceptions aside. So I would say no need to avoid unsweetened cocoa powder.

  4. My doctor told me once that there is some bacteria that lives by the hair follicle. Components of chocolate may be its food. When one eats chocolate the bacteria multiplies causing pimples.

    For the last 40 years once I eat some chocolate, I get pimples. 100%. If I remove hair that has a pimple or acne around I see a bacteria colony under a microscope. If I apply some alcohol to the open pimple, it NEVER gets swollen again after eating chocolate. I don’t know if there is a drug that could penetrate into skin and kill the bacteria that causes pimples breaking out after eating chocolate.

  5. I’m not surprised that chocolate causes acne. Firstly, it’s probably best to avoid it overall. If you are from a western country it’s not indigenous, meaning it’s imported and based off an entire capitalist child-enslavement scheme. Literally.

    It think people should get closer to the foods that are indigenous to their land in stead of supporting a long-running harmful industry.

  6. Cocoa is definitely a trigger food for me. That and dairy. Both have exactly the same effect on my skin, resulting in the big, hard, inflamed cystic type acne that Stephanie spoke of on my neck under my jaw. They both also act like switches. The smallest amount of either turns the acne on and with them eliminated my skin more or less completely clears up.

  7. Thanks for the information. We will have a debate tomorrow regarding to the chocolate causes acne myth. My other classmates answered yes because some study shows that chocolate causes pimples and acne, while the others who answered no said that chocolate do not have a high glycemic rate.

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