CLINICAL TRIALS AND THEIR INTERPRETATIONS (JR KIZER, SECTION EDITOR) Normal-Weight Obesity: Implications for Cardiovascular Health Nathalie Jean & Virend K. Somers & Ondrej Sochor & Jose Medina-Inojosa & Ernesto M. Llano & Francisco Lopez-Jimenez Published online: 24 October 2014 # Springer Science+Business Media New York 2014 Abstract We sought to review the epidemiological features and clinical implications of normal-weight obesity. The con- cept of normal-weight obesity has been recently reported as an important risk factor for cardiovascular disease, metabolic dysregulation, and poor functional outcomes. However, in clinical practice, normal-weight obesity is not commonly recognized. In this review, we examine the clinical signifi- cance and important epidemiological outcomes of normal- weight obesity and describe other variants of adiposity and adiposity-related metabolic status. The incorporation of mea- sures of body fat content and distribution in the clinical setting could allow more accurate identification of adiposity-related long-term risk. This could in turn lead to early lifestyle changes and behavioral modifications that are essential to the treatment of obesity. Keywords Obesity . Body mass index . Adiposity . Central obesity . Normal-weight obesity . Central obesity . Sarcopenic obesity . Cardiovascular diseases . Metabolic syndrome . Cardiovascular mortality Introduction The widespread availability and consumption of highly calo- ric food combined with increased inactivity has led to the current obesity pandemic [1]. The prevalence of obesity has been rising steadily in the last few decades. According to the World Health Organization (WHO), this phenomenon has reached alarming proportions. The USA leads the trend, with the highest prevalence of obesity worldwide; it is estimated that 78 million adult Americans were obese in 2011–2012 [2]. Over the last decade, there has been an increased interest in the study of obesity, its definition, diagnosis, and consequences. New concepts related to obesity have been introduced in recent years. One of these concepts is normal-weight obesity (NWO), a seemingly contradictory term that identifies people with normal body weight according to current definitions, but with an increased fat content. This article reviews the defini- tion, epidemiology, and implications of NWO for clinical practice. Obesity Definition The encyclopedia Britannica defines obesity as an “excessive accumulation of body fat, usually caused by the consumption of more calories than the body can use” [3]. Excess body fat This article is part of the Topical Collection on Clinical Trials and Their Interpretations N. Jean : V. K. Somers : O. Sochor : J. Medina-Inojosa : F. Lopez-Jimenez (*) Division of Cardiovascular Disease and Internal Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA e-mail: lopez@mayo.edu N. Jean e-mail: jean.nathalie@mayo.edu V. K. Somers e-mail: somers.virend@mayo.edu O. Sochor e-mail: sochor.ondrej@mayo.edu J. Medina-Inojosa e-mail: medina.jose@mayo.edu O. Sochor International Clinic Research Center, St. Anne’s University Hospital Brno, Brno, Czech Republic E. M. Llano University of Texas Southwestern Medical Center, Dallas, TX 75390, USA e-mail: ernesto.llano@utsouthwestern.edu Curr Atheroscler Rep (2014) 16:464 DOI 10.1007/s11883-014-0464-7