Angular stomatitis is a hallmark symptom of deficiency of which vitamin?

• A. Vitamin B3
• B. Vitamin B6
• C. Vitamin C
• D. Vitamin B2

Answer: (D)

Mucosal membrane health and rapid turnover depend on riboflavin (vitamin B2). Riboflavin is converted into the coenzymes FMN and FAD, which power many redox reactions essential for energy production and the maintenance of mucous membranes. When riboflavin is deficient, the lips and mouth become inflamed and fissures can form at the corners of the mouth, producing angular stomatitis. This presentation is a classic sign of vitamin B2 deficiency. Other deficiencies cause different patterns—niacin deficiency leads to pellagra (dermatitis, diarrhea, dementia), vitamin C deficiency causes scurvy (gum disease, poor wound healing), and vitamin B6 deficiency can also affect the lips but is not as specifically linked to angular stomatitis as riboflavin deficiency.