12 citations,
September 2018 in “International Journal of Cosmetic Science” Palmitoyl tetrapeptide-20 may help reduce hair greying and increase melanin production.
64 citations,
June 1992 in “International Journal of Dermatology” Pregnancy often causes skin changes like darkening, stretch marks, and hair growth, which may improve after childbirth.
46 citations,
July 1988 in “Journal of The American Academy of Dermatology” Hormone imbalances can cause specific skin changes, which may help in early detection of endocrine disorders.
12 citations,
January 1981 in “Springer eBooks” Environmental factors like temperature and nutrition affect hair growth, with humans showing seasonal hair growth differences.
5 citations,
May 2017 in “Journal of the European Academy of Dermatology and Venereology” The study found no significant difference in stress hormone levels between people with alopecia areata and healthy individuals, suggesting that the disease is not caused by an overactive stress response system.