This preclinical study published in 2019 presents insights into the importance of maintaining healthy biotin levels to prevent skin and hair changes often seen with zinc deficiency.
Ogawa Y, Kinoshita M, Sato T, Shimada S, Kawamura T. Biotin Is Required for the Zinc Homeostasis in the Skin. Nutrients. 2019 Apr 24;11(4):919. doi: 10.3390/nu11040919. PMID: 31022908; PMCID: PMC6520690.