Micronutrient Deficiencies in Patients Candidate for Bariatric Surgery: A Prospective, Preoperative Trial of Screening, Diagnosis, and Treatment

Bariatric surgery candidates often show preoperative micronutrient deficiency. Although it is documented that a comprehensive micronutrient assessment should be conducted preoperatively to correct the deficiencies before surgery, no previous studies have been effective in correcting deficiencies in sufficient time prior to surgery. Our aim was to identify micronutrient deficiencies preoperatively and correct them before surgery. 50 patients (18 female, 32 male) scheduled for bariatric surgery were assessed for micronutrient status 20 weeks prior to surgery. Baseline levels of vitamin B12, folic acid, 25-vitamin D, vitamin C, vitamin A, vitamin E, iron, zinc, magnesium, and selenium were measured. Data were compared with accepted clinical cutoff values. Patients found to have one or more micronutrient deficiencies were instructed to take daily micronutrient supplements specially formulated for obese patients and were evaluated every 5 weeks over a 20-week period. Nutrient intake was also evaluated before and after supplementation. Micronutrient deficiencies were observed in 40 patients (80 %, 13 female, 27 male). All 40 patients started prescribed supplementation immediately. 20 patients (10 female, 10 male) completed a follow-up at 20 weeks. Herein we found that 10 weeks of preoperative micronutrient supplementation is capable of effectively treating micronutrient deficiencies in our candidates for bariatric surgery. Considering that: 1) no new medication was allowed during the study; 2) patients already under pharmacological treatment did not change their therapy; 3) no statistically differences in nutrient intake were observed before and after the supplementation, we are confident to attribute the improvements in patients' micronutrient status directly to the supplement.