Study Enrollment Flow Diagram. Study enrollment opened July 2012. 67 CF cases were reviewed to determine eligibility. All cases were reviewed by 3 board-certified pulmonary and critical care physicians actively caring for adults with CF. 50 patients immediately met pre-determined exclusion criteria: actively infected, actively on intravenous antibiotics, recently had surgery, had gut issues or were known to be unreliable (>3 office no shows). 17 CF patients met eligibility criteria so were interviewed during the 3-month open enrollment period. Another 5 patients refused to participate due to distance from Philadelphia, concerns about meeting the requirements of the study, or were just not interested. Among the 12 patients that consented and began the trial, another 2 withdrew for personal reasons. Between July – November 2012, 10 CF patients completed the study.