To the Editor In their study on body mass index (BMI) associated with the lowest mortality in Denmark, Dr Afzal and colleagues1 concluded that the BMI associated with the lowest all-cause mortality increased by 3.3 (calculated as weight in kilograms divided by height in meters squared) over 3 decades and that optimal body weight was currently in the overweight category. We believe that their analysis has inherent biases and their conclusions may be misleading.
Shilpa N. Bhupathiraju, Walter C. Willett, Frank B. Hu. Body Mass Index and All-Cause Mortality. JAMA. 2016;316(9):991. doi:10.1001/jama.2016.10282