TLDR 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.
In a study involving 73 redhaired and 130 non-redhaired European individuals, researchers found that redhaired individuals had higher levels of the vitamin D precursor calcidiol in their blood serum, regardless of sun exposure or suntan intensity, suggesting a physiological difference rather than behavioral. The study also observed that folic acid levels were similar between redhaired and non-redhaired subjects, but increased with age and baldness intensity, and decreased with more frequent visits to tanning salons. The correlation between hair redness and calcidiol levels, measured by spectrophotometric methods and assessments by participants and observers, led to the suggestion that redheadedness may be an evolutionary adaptation to synthesize sufficient vitamin D in regions with lower UV-B radiation, such as central and northern Europe.
134 citations,
December 2018 in “Dermatology and Therapy” Some vitamins and minerals like vitamin D and iron can help with certain types of hair loss, but more research is needed for others.
79 citations,
January 2017 in “Dermatology practical & conceptual” Correcting nutrient deficiencies may help with hair loss, but the benefits of supplements without a deficiency are uncertain and could be harmful.
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33 citations,
April 2009 in “Clinical and Experimental Dermatology” Psychological factors like depression may be more important than zinc, folate, and vitamin B12 levels in causing scalp pain in people with hair loss.
5 citations,
June 2020 in “Experimental dermatology” Redheaded people may have evolved to efficiently make vitamin D in areas with less sunlight.
[object Object] 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 2017 in “Springer eBooks” Eating a balanced diet with specific nutrients can help manage menopause symptoms and prevent related health issues.
March 2014 in “Journal of The American Academy of Dermatology” The document lists various dermatology topics, treatments, and diagnostic methods.
2 citations,
April 2019 in “Acta medica Philippina/Acta Medica Philippina” People with alopecia areata often have lower vitamin D levels than healthy people.
