Micronutrients deficiencies and undernutrition after obesity surgery

Obese patient is at risk of undernutrition, due to specific deficiencies or sarcopenia. After bariatric surgery, the risk of nutritional deficiency depends on the weight loss and the type of surgery; restrictive procedures (as gastric banding) can induce digestive disorders, food intolerance and inappropriate dietary behaviors related to pre-or postoperative eating disorders. Low micronutrient intake during weight loss justifies a systematic supplementation with multivitamins with trace elements. Gastric bypass causes micronutrients. Sleeve gastrectomy leads to a lower risk of deficiency than gastric bypass but significant in the short term, justifying regular screening and supplementation. Iron deficiency is frequent after these three interventions and especially in non-menopausal women. Gastric bypass increases the risk of iron deficiency. Supplementation is not systematic but may be discussed in women before menopause. After gastric bypass, the malabsorption of calcium and vitamin D leads to a risk of accelerated osteoporosis, especially in women at the time of menopause. The risk of vitamin B12 deficiency is extremely high after gastric bypass and justifies systematic supplementation. Gayet-Wernicke encephalopathy is not uncommon, particularly in cases of food intolerance and prolonged vomiting. Regardless of the surgical technique, nutritional monitoring, appropriate supplementation and monitoring of patient adherence to these measures are required. These patients should therefore be monitored regularly and over the long term. (C) 2017 Association pour le developpement de la recherche en nutrition (ADREN). Published by Elsevier Masson SAS. All rights reserved.