research Effects of Hair Fibers on Braking Friction Materials November 2011 in “Advanced Materials Research” Adding 1% hair fibers to brake materials improves friction and wear, making them more effective.
research Estrogen Leads to Reversible Hair Cycle Retardation Through Inducing Premature Catagen and Maintaining Telogen 42 citations, July 2012 in “PLOS ONE” Estrogen can temporarily slow down hair growth but this can be reversed.