Metabolically Healthy Obesity and the Fit/Fat Phenotype: Associations with Mortality, Subclinical Cardiovascular Disease and Approach to Treatment

Obesity is a global epidemic affecting over a third of the adult population. Within the obese, subgroups have been identified, including the metabolically healthy obese (MHO) and the fit/fat phenotypes. The MHO phenotype was traditionally thought to have lower cardiovascular risk than the ‘typically obese’, a notion that is being challenged by recent data. Similarly, the emerging fit/fat phenotype is raising questions about the impact of obesity on mortality and cardiovascular risk. The present narrative review provides an overview of these phenotypes and summarizes current evidence and viewpoints regarding the same. The review then incorporates this data into a format that can be utilized by clinicians and researchers to aid clinical decision-making.