Is Being Underweight More Dangerous Than Being Overweight?

Being underweight is arguably more dangerous than being overweight, especially in older people. A BMI of 20 to 25 is usually associated with the longest healthiest life. Class 1 obesity is debatable; scientists argue about whether data shows significantly worse health outcomes for people in the overweight and class 1 obesity ranges. Ask your doctor to give you a better assessment if you really want to know where you stand.