Open questions about metabolically normal obesity

Subsets of obese subjects without any cardiometabolic risk factors have been repeatedly described. This raises questions whether obesity 'per se' enhances the risk for cardiovascular or metabolic diseases and whether healthy obese subjects would benefit from a medical treatment. In order to answer these questions, as a first step, an expert consensus should be reached for the definition of metabolic normality. In fact, up to now, different parameters related to the metabolic syndrome and/or to insulin sensitivity have been utilized across studies. Once an agreement is reached, population-based studies should be undertaken to establish the incidence of metabolic normality among obese subjects. Furthermore, many other parameters such as age, sex, race, fat distribution and physical activity should be monitored to obtain results representative of a general population. Longitudinal studies aimed at investigating the evolution of the cardiometabolic profile of healthy obese subjects are also needed. In conclusion, data from the literature strongly suggest that a regular surveillance of the cardiometabolic parameters and a prevention of any further weight gain should be applied to healthy obese individuals, whereas possible benefits of a weight loss treatment are still a matter of debate. International Journal of Obesity (2010) 34, S18-S23; doi:10.1038/ijo.2010.235