Cheilosis is a physical symptom associated with a deficiency of

• A. Vitamin D
• B. Folic acid
• C. Riboflavin
• D. Vitamin C

Answer: (C)

Cheilosis reflects a deficiency in riboflavin (vitamin B2), which is essential for maintaining healthy mucous membranes and skin. When riboflavin is lacking, the corners of the mouth (the lips) become cracked and inflamed, a classic sign known as angular cheilitis. Riboflavin functions as a cofactor in several redox reactions important for energy production and the integrity of epithelial tissues, so its shortage manifests in oral and facial mucosal symptoms like cheilosis, glossitis, and dermatitis.

The other options are less characteristically linked to cheilosis. Vitamin C deficiency causes gum disease and poor wound healing; vitamin D deficiency leads to bone-related issues; folic acid deficiency typically presents with macrocytic anemia and other mucosal changes but not the hallmark angular fissures of cheilosis.