Evidence check: SHBG in the context of skin aging

The link between SHBG (sex hormone-binding globulin) and skin aging is not firmly established. SHBG modulates the bioavailability of sex hormones like estrogen and testosterone, which influence collagen synthesis, skin thickness, and sebum production. Some observational studies suggest that lower SHBG in perimenopausal women may correlate with increased wrinkling and loss of elasticity, possibly due to a relative androgen excess. However, effect sizes are small, the evidence is heterogeneous, and confounding factors (e.g., BMI, insulin resistance) are often not fully controlled. Moreover, SHBG naturally increases with age, complicating causal interpretation. No robust randomized controlled trials directly address SHBG modulation for skin aging. Direct-to-consumer genetic tests that include SHBG variants (e.g., in the SHBG gene) tend to overstate clinical relevance. The evidence is primarily mechanistic and associative. Therefore, a single SHBG measurement or genetic score is insufficient to predict individual skin aging or to guide targeted anti-aging interventions. A comprehensive approach considering lifestyle, hormonal balance, and dermatological care is more appropriate.