To the Editor We welcome the research letter by Yang and Colditz,1 as it provides important information on temporal trends in the prevalence of body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared) subclasses by racial group from 1988 to 1994 and 2007 to 2012 in the United States. However, we feel it is important that greater discussion regarding the diverging trends in obesity subclasses by racial group is made, especially the difference in class III obesity (BMI ≥40) between non-Hispanic black women and non-Hispanic white women, over time.
Gearon E, Backholer K. Demographic Prevalence of Class III Obesity. JAMA Intern Med. 2015;175(12):2000-2001. doi:10.1001/jamainternmed.2015.6533