Bariatric surgery has emerged as a highly effective treatment not only for obesity, but also for type 2 diabetes (T2D). A meta-analysis has reported the complete resolution of T2D in 78.1% of cases of morbidly obese patients after bariatric surgery. Such extraordinary results obtained in diabetic patients with body mass index (BMI) scores>35kg/m² have led investigators to question whether similar results might be achieved in patients with BMIs<35kg/m². Preliminary studies suggest that metabolic surgery is safe and effective in patients with T2D and a BMI<35kg/m², whereas other studies report that metabolic surgery is less effective for promoting T2D remission in these patients. Thus, the results are discordant. Long-term studies would be useful for determining the safety, efficacy and cost-effectiveness of metabolic surgery for this population with T2D. In 2015, it is probably premature to say that metabolic surgery is an accepted treatment option for T2D patients with BMIs<35kg/m².