Protein-calorie malnutrition Quiz: Ace Your Exams

A 62-year-old woman presents to the primary care clinic to discuss recent weight loss. The patient has unintentionally lost 8% of her body mass over the past five months and has had reduced food intake for the past three weeks. Past medical history is significant for hypertension for which she takes lisinopril. The patient was screened for celiac disease last year because her sister told her she has a gluten intolerance. The patient’s small bowel biopsy was negative. The patient eats a vegetarian diet with a large amount of rice and beans. On physical examination, she is well-appearing, but her measured muscle mass is reduced. The patient has dentures that frequently fall out while she is talking. During the discussion and physical examination, she exhibits no features of disordered eating. On mental status examination, the patient has no signs of anxiety or depression. Which of the following is the most likely cause of this patient’s protein-calorie malnutrition?