# References

1. Daulatabad D, Singal A, Grover C, Chhillar N  
   Prospective analytical controlled study Evaluating serum biotin, vitamin B12, and folic acid in patients with premature canities. Int J Trichology. 2017;9(1):19-24. doi: 10.4103/ijt.ijt_79_16.  
   [Reference](https://pubmed.ncbi.nlm.nih.gov/28761260/)

2. Patel DP, Swink SM, Castelo-Soccio L.  
   A Review of the Use of Biotin for Hair Loss. Skin Appendage Disord. 2017;3(3):166-169. doi: 10.1159/000462981.  
   [Reference](https://pubmed.ncbi.nlm.nih.gov/28879195/)

3. Plonka PM, Handjiski B, Popik M, Michalczyk D, Paus R.  
   Zinc as an ambivalent but potent modulator of murine hair growth in vivo- preliminary observations. Exp Dermatol. 2005;14(11):844-53. doi: 10.1111/j.1600-0625.2005.00365.x.  
   [Reference](https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1600-0625.2005.00365.x)

4. Li Y, Han M, Lin P, He, Y, Yu J, Zhao R.  
   Hair growth promotion activity and its mechanism of Polygonum multiflorum. Evid Based Complement Alternat Med. 2015;517901. doi:10.1155/2015/517901.  
   [Reference](https://www.hindawi.com/journals/ecam/2015/517901/)

5. Han MN, Lu JM, Zhang GY, Yu J, Zhao RH.  
   Mechanistic studies on the use of Polygonum multiflorum for the treatment of hair graying. Biomed Res Int. 2015;651048. PMID:26640791  
   [Reference](https://pubmed.ncbi.nlm.nih.gov/26640791/)

6. Trüeb RM.  
   Pharmacologic interventions in aging hair. Clin Interv Aging. 2006;1(2):121-9. doi: 10.2147/ciia.2006.1.2.121.  
   [Reference](https://pubmed.ncbi.nlm.nih.gov/18044109/)