The concept of metabolic health, particularly in obesity, has attracted a lot of attention in the scientific community, and is being increasingly used to determine the risk of cardiovascular diseases and diabetes mellitus-related complications. This Review assesses the current understanding of metabolically healthy obesity (MHO). First, we present the historical evolution of the concept. Second, we discuss the evidence for and against its existence, the usage of different definitions of MHO over the years and the efforts made to provide novel definitions of MHO. Third, we highlight epidemiological data with regard to cardiovascular risk in MHO, which is estimated to be moderately elevated using widely used definitions of MHO when compared with individuals with metabolically healthy normal weight, but potentially not elevated using a novel definition of MHO. Fourth, we discuss novel findings about the physiological mechanisms involved in MHO and how such knowledge helps to identify and characterize both people with MHO and those with metabolically unhealthy normal weight. Finally, we address how the concept of MHO can be used for risk stratification and treatment in clinical practice.

代谢健康的概念，尤其是肥胖的概念，在科学界引起了广泛关注，并越来越多地用于确定心血管疾病和糖尿病相关并发症的风险。本综述评估了目前对代谢健康肥胖 （MHO） 的理解。首先，我们介绍这个概念的历史演变。其次，我们讨论了支持和反对其存在的证据、多年来 MHO 不同定义的使用以及为提供 MHO 的新定义所做的努力。第三，我们强调了有关 MHO 心血管风险的流行病学数据，与代谢健康正常体重的个体相比，使用广泛使用的 MHO 定义估计心血管风险中度升高，但使用 MHO 的新定义可能不会升高。第四，我们讨论了有关 MHO 所涉及的生理机制的新发现，以及这些知识如何帮助识别和表征 MHO 患者和代谢不健康正常体重的人。最后，我们讨论了如何在临床实践中将 MHO 的概念用于风险分层和治疗。