A constant plea from clinicians is for simplicity in any guidance, particularly when it is for a quick, simple, primary screening tool. The natural instinct of scientific researchers is to conduct and collate more research in the quest for precision and accuracy. Sometimes the time comes when a compromise must be reached. I believe the time has come regarding agreement on a proxy for central obesity, a well-recognized risk factor for cardiometabolic diseases. During the first decade of the 21st century, I argued, with colleagues from Japan, for the ‘urgency of reassessment of the role of central obesity indices for metabolic risks’(1). We suggested that waist-to-height ratio (WHtR) provides a very good screening tool for cardiometabolic risk (2) and we proposed the boundary value of 0.5 which converted into an easily remembered public health message:‘Keep your waist circumference to less than half your height’(3). Independently, Parikh and colleagues in India suggested that the Index of Central Obesity, namely the WHtR, should replace waist circumference (WC) in the definition of metabolic syndrome and also proposed a boundary value of 0.5 (4–6). Researchers in other parts of the world too, for example, Taiwan (7, 8), Iran (9), Chile (10) and China (11) have also advocated the use of WHtR to predict cardiometabolic risk. Those who have had the opportunity to study different ethnic groups within large populations in USA and UK (12, 13) have also proclaimed the potential of WHtR.

However, numerous screening tools for metabolic syndrome such as those produced by the World Health Organization (WHO)(14) and the National Cholesterol Education Programme Adult Treatment Panel III (NCEP ATPIII)(15, 16) only include one set of cut-off values for WC as a proxy for central obesity and do not specify different values for people of different races or regions. No recommended values of WC have been suggested for children, probably because this would be virtually impossible as WC will naturally increase with age. And yet, surely, early warnings of impending health problems are the most important?