What Is BMI? (video)

Body Mass Index tells if you’re at a healthy weight for your height

Body Mass Index tells if you’re at a healthy weight for your height

Ken Fujioka, MD, an endocrinologist and weight management specialist at Scripps Clinic Del Mar, explains Body Mass Index (BMI) and what it reveals about your health. Dr. Fujioka describes what is considered a good, normal and bad BMI.

Video transcript

What is BMI?

What is BMI?

BMI stands for Body Mass Index, which is a fancy mathematical formula to explain that as we get taller, you should get a little heavier, but not a lot heavier.


So we used to say who is normal weight and who is not. If you have a Body Mass Index, or a BMI, between 20 and 25, and you’re Caucasian or African-American, then you’re at a healthy weight. Twenty-five to 30 is overweight. Above 30 is considered seriously overweight or moving in the wrong direction.


Asians as a group don’t tolerate weight gain very well or they gain it viscerally, centrally. We’ve lowered the number. So now, they’re seriously overweight when their BMI is just 25. But again, it’s a way of measuring whether you’re normal weight, overweight or seriously overweight.

Is BMI different between men and women?

Is BMI different between men and women? It turns out no. And that’s something we need to remember. We always think, well women, they have less muscle, they should be lighter than men. If you have a man and a woman both, say 5'8" or 5'6", they should be the same weight to be healthy.

How do I calculate BMI?

If you want to calculate your BMI, it’s actually a tricky formula to use. What I would recommend is going through any of the websites that will calculate it for you. All you do is put in your height and your weight and it’ll figure out what your BMI is.

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