Short Chain Fatty Acid Metabolism in COPD

The short chain fatty acid (SCFA) metabolism has not been studied in subjects suffering from COPD. The purpose of this study is to compare the SCFA metabolism in COPD patients to healthy matched controls. This protocol is an extension of recent studies about protein digestion and absorption abnormalities in COPD patients. The investigators hypothesize that SCFA production might be lower in COPD patients than in healthy subjects.