I'm 6'0 and the last time I was under BMI 25 I was a triathlete. The only way I could be <25 would be to exercise 3 hours a day and eat 1200 calories. F-off and die
I did quit smoking though:
- Really wanted to - Picked a good mental argument against it ($100k CAD over 20 years) - Picked a quit date - Patch + zyban + nicotene lozenges
If you live in British Columbia, the government will pay for your patches or lozenges (hint: ask a friend)
If you're an athlete, or a bodybuilder, or particularly tall or small, it won't necessarily fit you. but if you're of normal-ish stature (ie 5'4 to 6'3), and don't keep track of your weight, it's probably bang on.
Every time I've taken BMI, the result is that I'm "slightly overweight". That's bullshit. If I actually tried to eat less, I'd probably end up having health complications related to malnutrition.
So BMI is very much bullshit when applied to individuals. It might have some relevance for the average case, and therefore be useful for demographic comparisons of large groups.
You could weigh 184 pounds and have a BMI <25. Even with a sedentary lifestyle you'd still burn 2,199 calories a day. This is patently false.