INTRODUCTION: Data already demonstrated the increased prevalence of obesity in various segments of the population. In this context, bariatric surgery is accepted nowadays as the most effective tool in the treatment and control of morbid obesity. Several studies have evaluated the nutritional status after bariatric surgery, especially mixed by detecting a reduction in food intake of protein, vitamins and minerals. However, other studies have investigated the presence of nutritional deficiencies prior to surgery, which may be aggravated by the surgical procedure, resulting in serious postoperative complications. AIM: To analyze the literature in relationship to micronutrient deficiencies in obese patients before bariatric surgery. METHOD: Was carried out a systematic review in several electronic databases, such as PubMed/ Medline, Scielo, Lilacs and Bireme. The following keywords were used alone or in combination: bariatric surgery, obesity, preoperative, gastric bypass, vitamin deficiencies, deficiencies and mineral nutrient absorption. Were included 40 review and original articles published between 2005 to 2012. RESULTS: There were consensus on the combination of preoperative nutritional deficiencies, restrictions and malabsorption, possibly induced by bariatric surgery that can lead patients to experience significant nutritional deficits during the late postoperative period, especially of micronutrients, resulting in serious complications. CONCLUSIONS: The high occurrence of micronutrient deficiencies preoperatively detected in morbidly obese candidates for bariatric surgery, plus a malabsorptive procedure, may involve worse prognosis during the late postoperative period. Preoperative evaluation of nutritional parameters and food intake is recommended in conjunction with surgical interventions.
Bariatric surgery; Obesity; Nutritional deficiencies; Preoperative; Micronutrient