 At any given time, about 85% of hair strands are in anagen.The fibroblast growth factor 5 (FGF5) gene affects the hair cycle in mammals including humans; blocking FGF5 in the human scalp (by applying a herbal extract that blocked FGF5) extends the hair cycle, resulting in less hair fall and increased hair growth.In ancient Greece, long male hair was a symbol of wealth and power, while a shaven head was appropriate for a slave.