Background: Canities, or hair graying, is believed to be driven by the cytotoxic effect of reactive oxygen species on follicular melanocytes, thus raising the concern that premature hair graying (PHG) may represent an outward sign of systemic oxidative stress.
Objective: This study aimed to identify the physiological, psychological, and lifestyle factors associated with PHG (defined as graying at age ≤30 years) in men and women.
Materials and methods: Data from 467 participants (female = 354 and male = 113; age: 18-77 years) were collected and analyzed, including demographic information, medical history, family history, supplement intake, and lifestyle factors.
Results: PHG was found to be significantly associated with a history of PHG in the mother, P<0.001, odds ratio (OR) = 3.165; father, P<0.001, OR = 5.166; maternal grandparent, P= 0.002, OR = 2.442; paternal grandparent, P= 0.007, OR = 2.369; and siblings, P<0.001, OR = 3.125. PHG was significantly associated with iron deficiency (P = 0.026, OR = 1.751) and family history of depression (P = 0.012, OR = 1.603), while herpes simplex virus infection (P = 0.004, OR = 0.367) and smoking history (P = 0.003) demonstrated significant negative associations. In Caucasians only (n = 306), in addition to these trends, irritable bowel syndrome was also significantly associated with PHG (P = 0.010, OR = 2.753). In Asians only (n = 75), history of heart disease in a first-degree relative (P = 0.038) was significantly associated with PHG.
Limitations: As a survey study, the findings may be subject to recall bias.
Conclusions: Important associations exist between PHG and family history of PHG, psychiatric history, supplement use, and vitamin deficiencies, providing insight into the pathophysiology and potential comorbidities of PHG.
Keywords: Canities; gray hair; premature hair graying.