Why lips turn dry?

•   Inadequate water intake to keep your skin hydrated.
•   Smoking.
•   Continuous exposure to sun, dust partials can also cause dryness.
•   Licking your lips often can cause dry lips.
•   Deficiency of vitamins A, B and C.
•   Intake of excess of Alcohol and caffeine removes moisture and causes dryness.
•   Some times cosmetics also contribute to dry lips.