Acne occurs most commonly during adolescence, affecting an estimated 80–90% of teenagers in the Western world. Lower rates are reported in some rural societies. In 2010, acne was estimated to affect 650 million people globally making it the 8th most common disease worldwide. People may also be affected before and after puberty.
There are some recent researches in this field like: Body mass index is negatively associated with acne lesion counts in Taiwanese women with post-adolescent acne. It can’t get access to the full text of this study, but it appears that researchers found evidence that heavier people have less acne than thin people.
Acne is affecting over 80% of teenagers (aged 13–18 years) at some point. Estimates of prevalence vary depending on study populations and the method of assessment used. Overall incidence of acne is similar in both men and women, and peaks at 17 years of age. The number of adults with acne, including people over 25 years, is increasing; the reasons for which are unclear.