research Congenital Hypotrichosis Due to Short Anagen Phase 42 citations, September 2000 in “British Journal of Dermatology” Some children are born with unusually short, fine hair because their hair growth phase is short, but this often gets better by itself during puberty.
research Reactive Keratin Derivatives: A Promising Strategy for Covalent Binding to Hair 20 citations, January 2019 in “Journal of colloid and interface science” Modified keratin binds better to hair, especially bleached hair.