Physical and/or mental disease or major surgery in the present or the past that might limit participation in or completion of the study
Reported current or previous metabolic (e.g. diabetes), cardiovascular and/or renal diseases
Known presence of a carcinoma
Acute and/or chronic inflammatory condition such as arthritis, arthrosis, chronic colitis, etc. during three months before entry of the study
Respiratory tract infection or exacerbation of COPD for at least 8 weeks prior to the start of the study
Change in treatment regime of the COPD subjects for at least 8 weeks prior to the start of the study
Use of laxatives, anti-diarrhoeal drugs and any other medication that can influence the uptake of the investigational products and/or influence their metabolism during the trial
During the month prior to the start of the study and during the study the use of antibiotics and/or local and systemic steroidal (glucocorticoids) and non-steroidal anti-inflammatory drugs (NSAID)
Abnormal constant dietary eating habits and a coffee consumption of less than 3 cups per day (i.e. a usual daily intake of \<400 mg caffeine).
