Is Progesteron useful for skin aging?

Progesterone is sometimes marketed in cosmetics and anti-aging medicine as a topical hormone to improve skin elasticity and reduce wrinkles. However, the scientific basis is weak. There are mechanistic hints that progesterone may influence collagen synthesis and skin barrier function, but robust human randomized controlled trials are lacking. Existing evidence comes mostly from in vitro or animal studies and small observational studies with high bias potential. Moreover, hormonal effects are highly dose- and individual-dependent; uncontrolled use can cause skin irritation or systemic effects. Without medical supervision and clear human evidence, recommending progesterone for skin aging is not justified. Those concerned with skin aging should rely on established measures like sun protection, retinoids, antioxidants, and a balanced diet. The overall evidence level is mechanistic/unclear.