# Biological and medical factors of hair pigmentation > Live situation record from CLSTR: https://clstr.news/situations/biological-and-medical-factors-of-hair-pigmentation > Updated: 2026-09-21T08:09:34.000Z. Sources: 4. Developments: 2. Medical and biological research has identified various factors influencing hair pigmentation and the onset of premature graying. Initial findings highlight lifestyle and medical contributors, noting that smokers are approximately 2.5 times more likely to experience graying before age 30. Other significant factors include chemical exposure from hair products, chronic stress, autoimmune diseases, thyroid dysfunction, and nutritional deficiencies in vitamins B6, B12, D, E, biotin, and iron. Further studies into biological mechanisms show that hair color transitions, such as blond children becoming brunettes, are driven by the intensification of eumelanin production by melanocytes. Research also suggests that the rate of graying may vary by hair color; specifically, individuals with darker hair may require higher concentrations of minerals like copper to support the pigmentation processes necessary to maintain color. ## Timeline ### 2026-09-21: Biological factors influencing hair pigmentation and graying Research explores why hair color changes with age, noting that many blond children become brunettes due to increased eumelanin production and how copper levels may influence pigmentation. 2 sources. https://clstr.news/cluster/biological-factors-influencing-hair-pigmentation-and-graying ### 2026-08-22: Medical factors linked to premature graying of hair Medical research identifies smoking, chronic stress, chemical exposure in hair products, and nutritional deficiencies, such as low iron and vitamins, as primary causes of premature graying. 2 sources. https://clstr.news/cluster/medical-factors-linked-to-premature-graying-of-hair --- Cite as: Biological and medical factors of hair pigmentation. CLSTR, https://clstr.news/situations/biological-and-medical-factors-of-hair-pigmentation