TLDR  Iron supplements can restore normal hair color in cases of premature graying linked to iron deficiency.   
  An 11-year-old male with premature hair graying, linked to iron deficiency anemia (IDA), was successfully treated with ferrous sulfate (40 mg/day) for 5 months, resulting in the restoration of normal hair color and improved serum ferritin and hemoglobin levels. This case highlighted the potential role of iron in hair pigmentation and suggested that ferritin level testing should be considered in patients with premature graying. The study underscored the need for larger, prospective studies to further explore the relationship between iron concentration and premature canities.
            35 citations
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  January 2013   in “International Journal of Trichology”
           35 citations
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  January 2013   in “International Journal of Trichology”    Kids with early graying hair often have low levels of calcium, ferritin, and vitamin D3.  
               26 citations
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  October 2011   in “Biological trace element research”    Low copper levels might cause premature graying of hair.  
    
  
        
        November 2018   in “Springer eBooks”
           November 2018   in “Springer eBooks”    Children need early diagnosis and treatment for iron-deficiency anemia to prevent learning problems and promote health.  
      207 citations
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  April 2006   in “Journal of The American Academy of Dermatology”
           207 citations
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  April 2006   in “Journal of The American Academy of Dermatology”    Iron deficiency may be related to hair loss, but there's not enough evidence to recommend iron screening or supplements for all hair loss patients.  
      1 citations
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  August 2023   in “Cutis”
           1 citations
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  August 2023   in “Cutis”    Low ferritin levels can indicate iron deficiency as a cause of hair loss.  
      30 citations
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  October 2010   in “Journal of The American Academy of Dermatology”
           30 citations
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  October 2010   in “Journal of The American Academy of Dermatology”    The conclusion suggests a possible link between iron levels and hair health in women, recommending further research on iron supplementation for hair loss.  
      May 2022   in “International Journal for Research in Applied Science and Engineering Technology”
           May 2022   in “International Journal for Research in Applied Science and Engineering Technology”    Iron supplements combined with Quilib lotion effectively treat hair loss in people with iron deficiency anemia.