Background: Dietary factors and smoking play a role in acne. Methods: CSA Santé conducted a survey in France in 2012. Each individual answered a questionnaire to report acne, with associated epidemiological variables. Data on subjects between 15 and 24 years of age were extracted. The characteristics of subjects reporting acne were compared to subjects reporting no acne, using univariate and multivariate analysis. Results: The daily consumption of chocolate and sweets was independently and highly associated with acne, with an odds ratio of 2.38 (95% CI: 1.31-4.31). Smoking more than 10 cigarettes a day was highly associated with no acne, with an odds ratio of 0.44 (95% CI: 0.30-0.66). The regular use of cannabis was associated with acne, with an odds ratio of 2.88 (95% CI: 1.55-5.37). Conclusion: Chocolate, sweets and cannabis smoking are associated with acne. We found tobacco to be protective. We failed to investigate the respective roles of sugar, lipids and milk.