In Search of the 70-kg Man

I remember only a small portion of what I was taught in medical school. The principles of pharmacology are a mere blur at this stage of my career. I have no recollection of how to calculate the volume of distribution of a drug after administration. Yet, I do remember that the 70-kg man was used as a reference for many such calculations. Interestingly, the concept of the “Reference Man” was developed by the International Commission on Radiological Protection in 1974 to assist in estimation and standardization of radiation exposure to individuals. A “standard man” was described as weighing 70 kg (154 pounds) and being 170 cm tall (5′7″). This individual would end up with a calculated body mass index (BMI) of 24.1 kg/m².

More than forty years have gone by since the “standard man” was defined. Over those four-plus decades, finding individuals (men or women) who conform to those measurements has become increasingly difficult. In the United States, individuals have become taller but their weight has increased much more dramatically. The Centers for Disease Control and Prevention estimates that on average men and women weigh 196 pounds and 169 pounds, respectively. More than 70% of adults in the United States are overweight (BMI ≥25-29 kg/m²), whereas nearly 40% of adults are obese (BMI ≥30 kg/m²).

In this issue of the Medical Clinics of North America, Drs Kahan and Kushner have enlisted experts from around the country to discuss the importance of recognizing obesity and its health consequences. The emphasis of this issue is on multimodality approaches to this highly prevalent chronic disease. It is hopeful that through this multimodal approach, the population as a whole will be able to break the trends in obesity rates and make the “standard man” appear more realistic.