PURPOSE OF REVIEW The continued success of bariatric surgery to treat obesity and obesity-associated metabolic conditions creates a need for a strong understanding of clinical nutrition both before and after these procedures. RECENT FINDINGS Surgically induced alteration of gastrointestinal physiology can affect the nutrition of individuals, especially among those who have undergone malabsorptive procedures. While uncommon, a subset of patients may develop protein-calorie malnutrition. In these cases, nutrition support should be tailored to the severity of malnutrition. Among all patients who undergo bariatric surgery, high rates of micronutrient deficiencies have been observed. To mitigate these deficiencies, empiric supplementation with multivitamins, calcium citrate, and vitamin D is generally recommended. Periodic surveillance should be performed for commonly deficient micronutrients, including thiamin (B1), folate (B9), cobalamin (B12), iron, and vitamin D. Following Roux-en-Y gastric bypass, serum levels of copper and zinc should also be monitored. In addition, lipid-soluble vitamins should be monitored following biliopancreatic diversion with/without duodenal switch.