January 2019 in “Figshare” Redheaded people have higher levels of vitamin D precursor, suggesting their hair color may be an adaptation to low sunlight areas.
January 2025 in “Digital Repository (National Repository of Grey Literature)” Red hair is linked to worse health, especially in women.
December 2019 in “bioRxiv (Cold Spring Harbor Laboratory)” Redheaded people have higher levels of a vitamin D precursor, suggesting red hair may be an adaptation for better vitamin D synthesis in areas with less sunlight.