BMI = [ weight (lb) / height (in)2 ] x 703
|Chart from CDC|
I like BMI since it accounts for the variable of height, making it a more uniform way of discussing a healthy weight than merely pounds. It doesn't, however, consider other factors such as muscle (muscle weighs more than fat - i.e., more muscle weight takes up less space) and bone structure, so you should take it with a grain of salt.
I'd like to think I have a decent amount of muscle (I can't do a pull-up, but I can do multiple real push-ups, so I would think that puts me marginally above average), so I take that in account in thinking about the health consequences of having a BMI in the overweight or obese categories. I think body measurements (relative to your height) and lab tests (e.g., cholesterol levels) are just are important as weight and BMI in looking at the whole picture of your health.
At my highest weight (about six months ago), I had a BMI of 32.61. 7 weeks ago, when I had just finished the 8-week Best Body Bootcamp my BMI was 30.27. Since then I've been training for my third half marathon and trying to do strength training at least twice a week.
My current BMI: 29.68!
I also realized this weekend that I need to replace my jeans - I can pull them down without unbuttoning them! I'm not big on sharing specific weights or sizes (to minimize opportunities for unhealthy comparisons with others) but I am proud that this will mean going from a 10 to an 8 in jeans - single digit size! Haven't worn 8s for 3 or 4 years.