Nutrition as a metabolic modulator in COPD.

COPD is an important global health problem. In addition to pulmonary impairment, systemic inflammation, musculoskeletal abnormalities, and cardiovascular comorbidity influence disease burden and mortality risk. Body weight and body composition are important discriminants in classifying disease heterogeneity. The rationale for and efficacy of caloric supplementation in preventing and treating involuntary weight loss is currently well established. For maintenance of muscle and bone tissue, appropriately timed, high-quality protein intake and addressing vitamin D deficiency must be considered. Specific nutrients (eg, n-3 polyunsaturated fatty acids and polyphenolic compounds) may have the pharmacologic potential to boost decreased muscle mitochondrial metabolism and enhance impaired physical performance, particularly when the metabolic stimulus of physical activity alone is limited. At this stage, evidence is insufficient to support an intake of high doses of single nutritional supplements to modulate respiratory pathology, but some small studies have identified micronutrient modulation via the diet as a promising intervention.