Cheilosis is cracking at the corners of the mouth; deficiency of which vitamin is most associated?

• A. Riboflavin
• B. Niacin
• C. Iron
• D. Pyridoxine

Answer: (A)

Riboflavin deficiency is tied to fragility of mucosal tissues because riboflavin (vitamin B2) is converted to its active coenzymes, FAD and FMN, which are essential for many redox reactions in energy metabolism. The oral mucosa has rapid cell turnover and high energy demands, so when this vitamin is lacking, the mucous membranes become inflamed and fissures can develop at the corners of the mouth, known as cheilosis. This classic mucosal sign often accompanies other riboflavin-related findings like glossitis and stomatitis.

Other options describe different patterns: niacin deficiency (pellagra) presents with dermatitis in sun-exposed areas, diarrhea, and dementia; iron deficiency can contribute to angular fissures but is not a vitamin deficiency; pyridoxine deficiency can cause stomatitis as well, but the characteristic association with cracks at the mouth corners is most strongly linked to riboflavin deficiency. Therefore, cheilosis is most associated with riboflavin deficiency.