A healthy BMI for a man is generally between 18.5 and 24.9. That said, if a man is leaner and has more muscle mass than average, it’s possible to be perfectly healthy despite having a BMI over 24.9. It’s rare to find a man who is healthy with a BMI of less than ~17, though.
Learn more:
The Truth About BMI Charts… (Isn’t What You Think)
The Absolute Best Way to Improve Your Muscle Definition
Why Belly Fat Is So Stubborn (and How to Lose It)