Cosmetic Habits Associated With Breast Cancer in Benin: A Multicenter Case–Control Study

ABSTRACT Introduction Breast cancer remains the leading cause of cancer‐related death among women worldwide. An increasing number of studies highlight the contribution of environmental and lifestyle factors, including cosmetic use, in its development. Objective To assess the association between cosmetic and dietary habits and breast cancer risk among women in Benin. Methods A case–control study was conducted involving 100 women diagnosed with breast cancer and matched 200 controls in the departments of visceral surgery, internal medicine, dermatology‐venereology, and rheumatology at CNHU‐HKM, and the gynecology‐obstetrics department of CHU‐MEL. Data were collected using a standardized questionnaire addressing family history, dietary patterns, and cosmetic product usage. Results In multivariate analysis, several cosmetic practices including the use of alkaline soaps (OR a = 7.26; p = 0.001), scented body lotions (OR a = 25.90; p < 0.001), perfumes (OR a = 30.43; p < 0.01), deodorants (OR a = 5.76; p = 0.009), shampoos/conditioners (OR a = 31.92; p < 0.001), and lipsticks (OR a = 69.12; p = 0.018) were significantly associated with increased breast cancer risk. First‐degree family history of breast cancer was associated with more than a threefold increase in risk. Contrary to existing literature, the consumption of soy, beans, and sesame also appeared to be linked to a higher risk of breast cancer in this population. Conclusion Our results show a possible association between environmental factors—particularly the use of cosmetic products—and breast cancer. These results underscore a compelling need for a national cosmetovigilance system in Benin and public health initiatives promoting healthier lifestyles, especially among genetically predisposed women.