A healthy body habitus is more than just a normal BMI: Implications of sarcopenia and sarcopenic obesity

Body mass index (BMI), calculated by measuring body weight and dividing by height squared, is traditionally used to categorise patients into healthy weight, overweight, or obese class I–III. This measure of nutritional status is then used to assess cardiovascular and metabolic disease risk. Some of the limitations of the BMI have been addressed with the recommendation to now also measure waist circumference [ [1] Janssen I. Heymsfield S.B. Allison B.D. et al. Body mass index and waist circumference independently contribute to the prediction of nonabdominal, abdominal subcutaneous, and visceral fat. Am J Clin Nutr. 2002; 75: 683-688 PubMed Google Scholar ], or waist to hip circumference ratio, to classify patients into low, moderate, or high risk for vascular disease. In a Caucasian population of 65–74 year olds, mortality risk was associated with an increased waist circumference (defined as >102 cm in men, >88 cm in women) irrespective of BMI category [ [2] de Hollander E.L. Bemelmans W.J.E. Boshuizen H.C. et al. The association between waist circumference and risk of mortality considering body mass index in 65–74 year olds: a meta-analysis of 29 cohorts involving more than 58,000 elderly persons. Int J Epidemiol. 2012; 2: 805-817 Crossref Scopus (88) Google Scholar ]. Muller and colleagues [ [3] Muller M.J. Lagerpusch M. Ederle J. et al. Beyond the body mass index: tracking body composition in the pathogenesis of obesity and metabolic syndrome. Obes Rev. 2012; 13: 6-13 Crossref PubMed Scopus (189) Google Scholar ] go further and suggest that body composition analysis is important. They suggest further subtypes of people who are thin on the outside, but fat inside (TOFI), metabolically healthy obese (MHO) or metabolically abnormal obese (MAO). In the latter two groups their BMI would be identical, providing strong evidence for the lack of use of BMI alone to assess metabolic syndrome risk.