Vitamin, status after gastric bypass and lifestyle intervention: a comparative prospective study

Background: Bariatric surgery can lead to vitamin deficiencies. We aimed to assess the changes in blood vitamin concentrations in patients who were taking predefined supplements after gastric bypass surgery. Methods: A total of 29 patients underwent gastric bypass and 24 unmatched controls underwent lifestyle intervention in a prospective, nonrandomized trial. The patients in the surgical group received multivitamin, iron, calcium, vitamin D, and vitamin B-12 supplements. No supplements were prescribed to the lifestyle group. The median body mass index decreased from 46 to 32 kg/m(2) after surgery and from 40 to 39 kg/m(2) after lifestyle intervention. Results: Of the 53 included patients, 50 completed the 1-year follow-up examination (94%). Compared with the lifestyle patients, the surgical patients had increased vitamin B-6, folic acid, vitamin B-12, and lipid-adjusted vitamin E (P <.02 for each) concentrations but decreased vitamin A concentrations (P <.01) during follow-up. No significant difference between the 2 groups was found for vitamin B-1, vitamin C, or 25-hydroxyvitamin D. Most surgical patients reported taking their supplements. Conclusion: Gastric bypass patients adhering to a set of dietary supplements had mostly stable or increased vitamin concentrations compared with both their baseline values and the changes in a nonsurgical control group. (Surg Obes Relat Dis 2012;8:169-175.) (c) 2012 American Society for Metabolic and Bariatric Surgery. All rights reserved.