Does Chocolate Cause Acne?

Does chocolate cause acne? The effect of chocolate on acne exacerbation has been debated many times in literature. The scientific answers are not yet unanimous; there is conflicting evidence. Some studies have shown no particular correlation between acne and chocolate consumption, and that it's not the chocolate itself that causes pimples. Analyses suggest that it is the additive ingredients (milk, sugars, etc.) contained in chocolate that contribute to the worsening of acne.

This consensus is based in particular on a famous study conducted by J. E. Fulton in 1969, which is often cited in the literature, establishing that there is no link between chocolate consumption and acne. In this study, he assessed the worsening of acne over 11 weeks in a group of subjects with pre-existing acne lesions (n = 65). They were asked to eat either a chocolate bar or a placebo bar rich in fats, sugars and no chocolate each day. The study concluded that chocolate consumption had no greater influence on the appearance of new acne breakouts than its substitute. However, this study had numerous flaws: the short duration of the experiment, an inappropriate control that contained as much sugar and fat as the chocolate bar, the method of counting skin lesions, and the absence of data on the severity of the lesions observed.

Later, another study evaluated the effect of fifteen jelly beans and one chocolate bar on the skin of fifty-six students. It concluded that chocolate ingestion did not contribute to the appearance of new skin lesions. However, this study was also flawed: the chocolate bar distributed contained sugars and milk, foods that aggravate acne. Thus, the link between the development of new lesions of acne and chocolate replaced by the theory that a high glycemic load can affect acne formation. Thus, these results are not strong enough to draw any conclusions.

However, this dogma was later challenged. Until now, there have been no clinical studies on the direct effect of 100% cocoa on pimple formation. However, recent studies support the idea that worsening acne may be linked to chocolate consumption. In one study, male volunteers with a history of acne ingested 340 grams of 100% chocolate at once, while maintaining a normal diet for a week. After 4 and 7 days, a statistically significant increase in the average number of total acne lesions (papules, nodules, comedones, pustules) was observed compared with the start of the study. However, the design of this study has several limitations: small sample size (n = 10), absence of a control group and short study duration.

Another research study from 2016 also aims to examine the effects of dark chocolate on the exacerbation of existing acne. Twenty-five men (thus excluding the effects of female hormones and premenstrual flare-ups) with acne-prone skin consumed chocolate with 99% cocoa daily, eliminating the effects of sugars and milk. After four weeks of chocolate consumption, the number of acne lesions increased significantly, particularly the number of comedones and inflammatory papules.

A similar experiment was conducted in 2014 on men with a history of acne. They were asked to swallow a large quantity of capsules filled with either 100% unsweetened cocoa powder, hydrolyzed gelatin, or a combination of the two in different proportions. The result was the same: an increase in the number of inflammatory and non-inflammatory lesions was observed. It would thus appear that in acne-prone males, that an aggravation of acne and chocolate consumption is correlated. However, this study was carried out on a smaller number of subjects (n = 14).

The limitations of these studies are that they only involve individuals with a pre-existing acne problem. Does chocolate cause acne in people who are not prone to this issue? Moreover, the fact that chocolate worsens acne is not certain, given the small number of studies. Cocoa contains large quantities of flavonoids, known for their antioxidant and anti-inflammatory properties. Dark chocolate also contains cocoa butter, which comprises, among other things, 33% monounsaturated oleic acid and 33% stearic acid. But oleic acid has been shown to modify the keratinization of the epithelium, leading to the formation of comedones.