TLDR  A 31-year-old man's hair turned white suddenly, likely due to alopecia areata.   
  A 31-year-old man experienced a sudden whitening of his scalp and body hair, which might be related to alopecia areata and its underlying mechanisms.
            29 citations
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  June 2013   in “Journal of the Saudi Society of Dermatology & Dermatologic Surgery”
           29 citations
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  June 2013   in “Journal of the Saudi Society of Dermatology & Dermatologic Surgery”    Alopecia areata is an autoimmune hair loss condition treated with corticosteroids, and histologic confirmation is the best diagnosis method.  
    
  
        
      November 2023   in “British Journal of Dermatology”
           November 2023   in “British Journal of Dermatology”    Different people with severe hair loss respond to baricitinib treatment at different times, with some showing improvement early, some gradually, and others later.  
               May 2018   in “Journal of cosmetology & trichology”    Combining platelet-rich plasma therapy with prostaglandin-F eye drops can significantly regrow hair in alopecia universalis.  
      22 citations
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  January 2017   in “Indian Dermatology Online Journal”
           22 citations
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  January 2017   in “Indian Dermatology Online Journal”    Body hair transplants can treat baldness but differ from scalp hair and need more research on long-term results and side effects.  
               7 citations
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  July 2011   in “Archives of Dermatology”    Alopecia areata caused a boy's hair to regrow straight instead of curly, but the exact reason is unknown.