The Contribution of Endogenous and Exogenous Factors to Male Alopecia

The study, conducted on 92 identical male twins from 2009 to 2011, found that both genetic and environmental factors contribute to male alopecia. Environmental factors such as smoking, exercise, alcohol consumption, and spending on hair loss products were significantly associated with hair loss patterns. Higher testosterone levels were linked to increased vertex hair loss but were protective against temporal hair loss. Lower body mass index was associated with higher hair thinning scores, possibly due to higher free testosterone levels. The study suggests that lifestyle modifications could help manage male alopecia and that these factors could influence the outcome of hair transplantation. However, the study's limitations include a small sample size and reliance on self-reported data. Despite these limitations, the use of twins provided a genetic control, adding validity to the findings.