Low-level light therapy may reduce hair loss and improve hair quality but it's unclear who benefits most.
May 2021 in “Journal of Dermatology and Cosmetic” Low-power lasers can prevent hair death and increase hair growth in wounds caused by freezing in rats.
April 2019 in “Journal of Investigative Dermatology” Low-level laser therapy helps hair growth and reduces hair loss with few side effects.
54 citations
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June 2001 in “The Indian Journal of Pediatrics” Lower hair zinc levels may be linked to Neural Tube Defects.
2 citations
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May 2022 in “Diagnostics” Vitamin D levels in hair don't match those in blood, so hair isn't a reliable indicator of Vitamin D status.
1 citations
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October 2023 in “The Journal of nutrition, health & aging” Higher hair levels of zinc and chromium were linked to less cognitive decline in very old people.
November 2024 in “Psychoneuroendocrinology” Testosterone increases hair testosterone levels, stress raises hair cortisol, and relationship status affects hormone levels.
May 2023 in “Minia Journal of Medical Research” Vitamin D levels in hair and serum are similar for males and females.
37 citations
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March 2014 in “Journal of Trace Elements in Medicine and Biology” Lower hair zinc and copper levels found in Turkish males with hair loss; higher BMI linked to less hair zinc.
36 citations
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October 2008 in “European journal of paediatric neurology” Valproic acid treatment may cause temporary hair loss due to reduced zinc and biotinidase levels, which tend to normalize after 6 months.
21 citations
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November 2017 in “Archives of Dermatological Research” Higher enzyme levels found in women with hair loss, suggesting hormone imbalance.
16 citations
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May 2020 in “Psychoneuroendocrinology” People with Parkinson's disease have higher levels of cortisone in their hair, which may indicate chronic stress hormone dysfunction.
2 citations
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January 2011 Zinc deficiency may contribute to alopecia areata and vitiligo.
Higher cortisol levels might be linked to worsening keratoconus.
January 2016 in “American Journal of Clinical and Experimental Medicine” Lower zinc levels in hair are linked to more severe male pattern baldness, but blood zinc levels don't show this link. Age also increases baldness severity.
18 citations
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May 1992 in “American Journal of Biological Anthropology” Higher androgen levels do not cause baldness in men.
October 2025 in “Medical Journal of Babylon” Higher testosterone and lower Vitamin D levels are linked to hair loss in female COVID-19 patients.
July 2024 in “Occupational Medicine” Higher cortisol levels are linked to poor coping, while higher DHEA levels are linked to job confidence.
January 2024 in “İstanbul Kuzey Klinikleri” Low ferritin levels are linked to increased hair loss; no link found between vitamin B12, TSH levels, and hair loss.
Trichoriboside treatment helps maintain scalp hair by increasing cAMP levels in hair follicles of men with hair loss.
147 citations
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January 2014 in “American Journal of Clinical Dermatology” Laser device increases hair density, safe for treating hair loss in men and women.
71 citations
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January 2016 in “International Journal of Trichology” Biotin deficiency is not a major cause of hair loss in women, so biotin supplements are not likely to be an effective hair loss treatment.
44 citations
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May 2014 in “The American Surgeon” Low zinc and iron levels can predict hair loss after sleeve gastrectomy in women.
35 citations
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January 2001 in “Journal of Animal Science” High dietary selenium, especially inorganic, causes weight loss and selenosis in pigs, with effects varying by hair color.
17 citations
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January 2013 in “Indian Journal of Pharmacology” High levels of the seizure medication sodium valproate can cause hair loss.
10 citations
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April 1965 in “Journal of Nutrition” Changing mineral levels in rats' diets can prevent kidney stones, affect hair growth, and influence weight gain.
5 citations
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May 2024 in “Developmental Cell” Lower GATA3 levels in mice help hair regrow by changing certain immune cells.
1 citations
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February 2022 in “Open Access Macedonian Journal of Medical Sciences” Low zinc levels might contribute to early hair graying.
1 citations
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September 2021 in “Mağallaẗ Kulliyyaẗ al-ṭibb Baġdād” Low vitamin D levels may cause hair loss in women.
1 citations
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January 2021 in “Journal of Dhaka Medical College” Lower iron levels are linked to longer hair loss.