Having chapped lips may stem from your diet or beverages you consume. You might notice a severely dry upper lip shortly after enjoying your morning brew or within hours of eating a chocolate bar. If you think a specific food or drink is affecting the delicate skin around your mouth, stop consuming it and consult your health care provider. Chapped lips may be unrelated to your diet.

Drinking a piping hot cup of coffee or tea first thing in the morning may burn the tender skin, causing chapping. This effect is unrelated to the caffeine in the beverage; rather, it stems from the temperature of your caffeinated drink. Try sipping your beverage through a straw, which keeps the hot liquid away from your upper lip, eliminating burns.

Consuming large amounts of caffeine may also make you dehydrated. Caffeine acts like a diuretic in your system, pulling water and excreting it through urine. You may notice that you use the bathroom frequently after having several caffeinated beverages. When you become dehydrated, your skin dries out, including the skin on your upper and lower lips. Even though caffeine may make you dehydrated, you have to ingest large amounts for it to have this effect. Consuming upwards of 500 to 600 milligrams of caffeine each day affects your hydration levels, explains Katherine Zeratsky, a registered dietitian for the Mayo Clinic. This amount of caffeine is equivalent to drinking 5 to 7 cups of coffee.

Because a high caffeine intake can increase fluid loss, you may lose a large amount of water-soluble vitamins through urine. Water-soluble vitamins include a group of B vitamins, as well as vitamin C. These vitamins do not stay in your body. Your system automatically flushes them out when you consume a lot of liquid or when caffeine pulls fluid from your body. Vitamin C helps build collagen, which is a component of skin tissues, explains the Colorado State University Extension website. It is essential for repairing skin and building new skin cells. Inadequate levels of vitamin C in your body may increase your chances of dry, damaged skin, leading to a dry chapped upper lip.

Your body naturally expels saliva when you have food or drinks in your mouth. Saliva aids in digestion by breaking down food and making it easy to swallow. As you sip on a cup of coffee or chew on a chocolate bar, both of which contain caffeine, you may notice more saliva in your mouth. This effect may cause you to lick your lips more than normal. The more you lick your lips, the drier they become, says Lawrence E. Gibson, a dermatologist with the Mayo Clinic. Drinking water or brushing your teeth after you eat helps get rid of food particles in your mouth. This way, you won't have as much saliva in your mouth, and you will be less likely to lick your lips.