A recent Canadian study has found certain BMI ranges to be more or less correlated with mortality, and quite counter-intuitively the study found that being overweight to mildly obese is the least risky – even somewhat less risky than having a normal BMI.
- Underweight, BMI less than 18.5; relative risk (RR) = 1.73, a significantly increased risk of death
- Overweight, BMI 25-30; RR = 0.83, a significantly decreased risk of death
- Obesity class I, BMI 30-35; RR = 0.95, neutral
- Obesity class II+ , BMI over 35; RR = 1.36, an increased risk of death