Sebaceous gland diseases are a group of common dermatological diseases with multiple causes. To date, a systematic report of the risk factors for sebaceous gland diseases in adolescents has not been published. The aim of this study was to assess the prevalence and risk factors for certain sebaceous gland diseases (seborrhea, seborrheic dermatitis, acne, androgenetic alopecia and rosacea) and their relationship to gastrointestinal dysfunction in adolescents. From August-October, 2002-2005, a questionnaire survey was carried out to obtain epidemiological data about sebaceous gland diseases. Using random cluster sampling, 13 215 Han adolescents aged 12-20 years were recruited from four countries or districts (Macau; Guangzhou, China; Malaysia; and Indonesia). The statistical software SPSS ver. 13.0 was used to analyze the data. The prevalence of seborrhea, seborrheic dermatitis, acne, androgenetic alopecia and rosacea was 28.27%, 10.17%, 51.03%, 1.65% and 0.97%, respectively. Based on multivariate logistic regression analysis, the risk factors for sebaceous gland diseases included: age; duration of local residency; halitosis; gastric reflux; abdominal bloating; constipation; sweet food; spicy food; family history of acne; late night sleeping on a daily basis; excessive axillary, body and facial hair; excessive periareolar hair; and anxiety. There was a statistically significant difference in the prevalence of gastrointestinal symptoms (halitosis; gastric reflux; abdominal bloating; constipation) between patients with and without sebaceous gland diseases (chi(2) = 150.743; P = 0.000). Gastrointestinal dysfunction is an important risk factor for diseases of the sebaceous glands and is correlated with their occurrence and development.