Chocolate causes acne
The relationship between chocolate and acne has been debated for over half a century. An influential 1969 study found no link and was long treated as definitive, but more recent, better-designed trials have found that chocolate consumption may increase acne lesions in some people, possibly through glycemic or inflammatory mechanisms rather than a unique property of chocolate itself.
What we know
The scientific investigation of chocolate and acne dates to a landmark 1969 study published in JAMA, which for decades was treated as the definitive word on the subject. In that trial, participants were given either chocolate bars or visually identical placebo bars matched for calories and fat content, and researchers found no measurable difference in acne severity between the two groups. This result led much of the dermatological community to dismiss the chocolate-acne connection as folklore for the following several decades, and "chocolate does not cause acne" became a standard talking point in dermatology.
In retrospect, the 1969 study had significant methodological limitations that later researchers have highlighted. The sample size was small, the placebo bars used cocoa butter (a component of real chocolate) in their formulation, which may have blunted any true difference between groups, and the study did not isolate specific mechanisms that might link chocolate to acne through pathways other than fat and calorie content, such as glycemic load or specific bioactive compounds in cocoa.
More recent, better-controlled research has reopened the question with results pointing the other way. A 2016 study found a statistically significant increase in facial acne lesions among college-age participants measured 48 hours after chocolate consumption, compared to a control group given jelly beans matched for sugar content: the chocolate group averaged an increase of 4.8 lesions, while the control group averaged a decrease of 0.7 lesions, a striking divergence. A separate double-blind, placebo-controlled study conducted on young men with existing acne found increased numbers of comedones (clogged pores) and inflammatory pustules after they consumed pure chocolate compared to a placebo, using a design intended to isolate chocolate itself from confounding sugar or dairy content.
The proposed mechanisms behind this more recent evidence remain a subject of ongoing research and some disagreement among dermatologists. One leading hypothesis centers on glycemic index: milk chocolate in particular has a relatively high glycemic index, and diets high in high-glycemic-index foods have separately accumulated more consistent evidence as an acne aggravator, likely through their effect on insulin and insulin-like growth factor 1 (IGF-1) signaling, both of which can stimulate sebum production and skin cell proliferation implicated in acne formation. A second hypothesis points to specific bioactive compounds in cocoa itself that may have pro-inflammatory effects on skin, independent of sugar content, though this pathway is less well characterized. Dark chocolate, which has a comparatively lower glycemic index and higher cocoa concentration relative to sugar and milk solids, has not been as consistently implicated as milk chocolate in the newer trials, though data specifically isolating dark chocolate remain limited.
The current, more nuanced scientific consensus, reflected in a 2024 review in the journal Foods, is that a chocolate-acne link is biologically plausible and has some experimental support, but the overall evidence base remains inconsistent in magnitude and mechanism, and any effect is likely to be modest and to vary meaningfully between individuals. Acne is a multifactorial condition driven primarily by hormonal fluctuations (particularly androgens), genetic predisposition, sebum production, and colonization by Cutibacterium acnes bacteria, with diet functioning at most as a secondary contributing factor for some people rather than a primary cause for everyone. This is why the claim is classified as mixed rather than clearly true or false: the 1969 dismissal was premature, but the newer evidence does not support a sweeping claim that chocolate reliably causes acne in the general population either.
Common claims
- Chocolate has no effect on acne, according to science.Outdated
- Eating chocolate can increase acne lesions in some people.Partly supported
- High-glycemic foods in general may worsen acne.Accurate
- Dark chocolate has the same acne effect as milk chocolate.Not established