Common causes of cracked mouth corners include dry or cold weather, sunburn, wind exposure, licking your lips, and breathing through your mouth. In some cases, conditions such as the common cold, anemia, dehydration, and nutritional deficiencies may also result in cracked mouth corners.

What causes splits at side of mouth?

Saliva gets trapped and builds up in the corners of your mouth. When it dries, the skin in the area can crack. You may lick your lips often to soothe your cracked skin. The warmth and moisture in the corners of your mouth create the perfect conditions for fungus to grow and multiply -- and cause infection.

Which vitamin deficiency causes cracks at side of mouth?

1: Cracks at the corners of your mouth. The Deficiency: Iron, zinc, and B vitamins like niacin (B3), riboflavin (B2), and B12. "It's common if you're a vegetarian to not get enough iron, zinc, and B12," Blum says. Ditto if you're skimping on essential immunity-building protein due to dieting.