Smoking, UV rays, allergies and caffeine are some of the reasons which cause dark dry lips.
Olive oil and honey have been used since ancient times by women to lighten their lips and keep them soft.
Olive oil – Massage some warm olive oil on lips for 2 minutes at night before going to bed and rinse with warm water using cotton the next morning.
Honey – Apply a layer of honey on lips and leave overnight. The next day take some cotton and wet with warm water and gently wipe lips to remove any traces of honey.
Strawberries – Extract 2 teaspoons strawberry juice from a few fresh strawberries. Mix this with 4 teaspoons petroleum jelly (Vaseline). Apply on lips. Leave overnight and remove the next morning using cotton and warm water.