Next to each hair is a sebaceous gland which secrete sebum which lubricates the hair and provides each hair with an element of protection. If the sebaceous glands are overactive greasy or oily hair will result. If the glands are underactive dry hair may result including breakage.
Daily Hair Tip
If you lie on your back while you sleep this could cause hair stress leading to split ends in the back. To avoid hair stress tie hair back using a soft scrunchie band.