Preoperative nutritional deficiencies: epidemiology and prevalence of nutritional deficiencies among morbidly obese patients, specifying which ones should be supplemented

Abstract Micronutrient deficiency is common in obese patients admitted for bariatric surgery, especially, a considerable prevalence of low levels of vitamin D, folic acid, vitamin B1, vitamin B12, vitamin A, vitamin E, zinc, iron, and selenium has been demonstrated. Patients who are candidates for bariatric surgery usually present various factors that cause the appearance of these deficiencies (inappropriate eating behavior, alcohol consumption, chronic subclinical infiammation, several diseases, and medications that can impact the blood levels of micronutrients). This higher prevalence of micronutrient deficiencies in obese people could also promote postoperative complications and postoperative nutritional deficiencies. Therefore, evaluation and treatment of possible deficiencies are required preoperatively, and the evaluation of the patient with morbid obesity should be considered from a multidisciplinary perspective. All these deficiencies are capable of being corrected with an adequate supplement and management of the preoperative diet.