The transition of hair color from blonde in childhood to darker shades in adulthood is a natural process driven by genetics, melanin production, and hormonal shifts. Hair color is determined by two main types of melanin produced by melanocytes in the hair follicles: eumelanin, which creates brown and black tones, and pheomelanin, which contributes yellow and red hues.
Research indicates that at least 124 genes play a role in determining hair color. While scientists understand much about these genes, the exact mechanism of how follicles react to hormonal changes remains a subject of study. For many, the most significant darkening occurs around puberty, typically between the ages of 10 and 13, as rising levels of hormones like estrogen and androgens may stimulate increased eumelanin production.
Desmond Tobin, a professor of dermatology at University College Dublin, notes that the outcome depends heavily on genetic heritage. While some individuals maintain light hair throughout their lives due to low eumelanin production, others experience a gradual darkening as their follicles begin producing more pigment.
Entities
Dezmond Tobin · Jagiellonian University · University College Dublin · Wojciech Branicki