BMI, formula for this
 

Does anyone know the formula for figuring your BMI? I had a website open that would figure it for you, but forgot how to find it. I have a problem with getting a true number, because my height has changed so much. When I was younger I was 5ft 6inches tall. I have gradually gotten almost 5 inches shorter due to a bad spine. Double Scoliosis, also twisted badly. I think I should still use my former height in figuring my BMI, and not my current height, because I cannot stand up straight. I used the site I mentioned, and it said I was Overweight when I used current height. But it said Healthy Weight when I used my former height. Confusing!

I agree with you, you should use your former height. You are still that tall!

you divide your weight in pounds by height in inches squared, then multiply that number by 703. Example:
weight =150lbs; Height = 5'5" (65")
BMI calculation: (150 + (65)squared) X 703 = 24.96

This formula was on a paper I got from my doctor.

Those formulas and charts assume you have 'average' muscle mass. You also have to take that into consideration. If you have more muscle (heavier than fat), the charts may show your BMI to be higher than it actually is. Likewise if you have less muscle mass than average, it may show your BMI to be lower than it actually is.

you can get if from this ( nih.gov )

You should use your original height. A yard of ribbon loosely curled is still 36" long when straightened out. If you could straighten your spine, you would still be 5'6" tall. This said however, does your spine curvature affect your breathing? If it does, extra weight may compound the problem. Just thinking about this, I am not a medical professional.

No, it has not affected my breathing, but sometimes when I am seated my back brace does force me to lean back more than I feel comfortable doing. Maybe breathing does get in the picture in that situation. If so, it is not too bad.
I usually take my brace off when I want to sew awhile, as it is too awkward to have to lean back.
I thank all of you for help in figuring the BMI. I intend to save those directions for that, so I can keep up with my numbers.
The last time I was measured for height at doctors office was just before I got the last bone density checkup. I have osteopenia the last 2 checkups, hope it does not go on to worse.