Which nutritional component should be added to the diet of a patient with COPD?

• A. Fats
• B. Carbohydrates
• C. Protein
• D. Calories

Answer: (C)

In COPD, preserving lean body mass and supporting respiratory muscles is crucial because the disease creates a catabolic state with increased energy expenditure from the work of breathing and ongoing inflammation. Protein provides the essential amino acids needed for muscle protein synthesis, helping to prevent loss of respiratory muscle strength and overall muscle wasting. While total calories are also important to meet energy needs, a higher proportion of calories from protein supports muscle preservation without driving up CO2 production as much as a high-carbohydrate load might, which can worsen ventilation in COPD. Aiming for adequate calories with increased protein intake (roughly 1.2–1.5 g/kg/day, adjusted as needed) helps maintain respiratory muscle function and improves outcomes, making protein the best nutritional addition in this context.