Relative to normal weight, grades 2 and 3 obesity were associated with significantly higher all-cause mortality. Grade 1 obesity overall was not associated with higher mortality, and overweight was associated with significantly lower all-cause mortality. Summary Random-Effects Hazard Ratios (HRs) of All-Cause Mortality for Overweight and Obesity Relative to Normal Weight BMI Criteria Summary HR Underweight BMI of ≤18.5 ≫1.00 Normal Weight BMI of 18.5-<25 1.00 Overweight BMI of 25-<30 0.94 Grade 1 obesity BMI of 30-<35 0.95 Grades 2 and 3 obesity BMI of ≥35 1.29