Photo Credit Purestock/Purestock/Getty Images. Conditioning your hair with eggs enhances hair growth because eggs contain lots of protein. Hair is composed of 70 percent keratin protein, so egg protein helps rebuild damaged hair by filling in weakened spots along the hair strand, which temporarily strengthens the hair.Eggs contain a large amount of protein--ranging from 3.6 to 6.5 g per egg--which makes egg conditioning an intense protein treatment.Including egg conditioning in your hair regiment can help you maintain strong hair, which is essential for growth.air is composed of 70 percent keratin protein, so egg protein helps rebuild damaged hair by filling in weakened spots along the hair strand, which temporarily strengthens the hair. Eggs contain a large amount of protein--ranging from 3.6 to 6.5 g per egg--which makes egg conditioning an intense protein treatment.