Letters Section Editor: Jody W. Zylke, MD, Senior Editor.
Author Affiliations: Department of Nutrition, Harvard School of Public Health, Boston, Massachusetts (Drs Willett and Hu) (email@example.com); and Surveillance and Epidemiology Research, American Cancer Society, Atlanta, Georgia (Dr Thun).
To the Editor: In their meta-analysis of BMI and mortality “to inform decision making in the clinical setting,” Dr Flegal and colleagues1 found that mortality was not increased up to a BMI of less than 35.
We believe their study is flawed. Their comparison group (BMI of 18.5-<25) contains persons who are lean and active, heavy smokers, frail and elderly, and seriously ill with weight loss due to their disease, as well as Asian populations historically undernourished and burdened by infectious diseases.
Willett WC, Hu FB, Thun M. Overweight, Obesity, and All-Cause Mortality. JAMA. 2013;309(16):1681-1682. doi:10.1001/jama.2013.3075