Micronutrient deficiencies and sleeve gastrectomy for weight reduction.

Bariatric surgery is considered one of the most effective and durable tools in the treatment and control of morbid obesity. Sleeve gastrectomy (SG) is actually one of the most performed bariatric procedures. Micronutrient deficiency is common in obese patients admitted for SG, with a reported prevalence in low levels of 25-vitamin D, folate, vitamin B1, vitamin B12, vitamin A, vitamin E, zinc, iron, and selenium. In addition, although SG does not cause malabsorption, it appears to alter micronutrient status, in particular of iron and vitamin B12 levels. Compounding the problem, SG may exacerbate pre-existing micronutrient deficiencies and may render obese patients prone to other severe conditions, most commonly anemic, metabolic, and especially neurological disorders. In conclusion, preoperative micronutrient assessment and a rigorous postoperative follow-up plan with administration of multi-vitamin and mineral supplements, and assessment of serum levels, is recommended after all bariatric procedures, even for restrictive procedures such as SG.