Dark lips are an effect of sun exposure, excessive caffeine intake, hormonal imbalances, certain allergies or harmful UV rays. Smoking and cigarettes are one of the common most reasons for dark lips. The produced heat, presence of tobacco and tar, damage to capillaries and lack of oxygen supply due from smoking blackens the lips and the areas around it. Lips also tend to darken with age. Lemon being a bleaching agent, used for skin lightning treats the pigmentation on lips. Ingredients such as honey soften the surface and help lighten them. Petroleum jelly serves as a repairing agent and moisturizes the lips. Beetroot is a great contributor to moisturize and nourish the skin.