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• Weight Loss Surgery Center
• Meet the Team
• Program Highlights
• Referring a Patient
• Making an Appointment
• About Obesity
  • What is BMI?
• Surgical Options
• Weight Loss Quality and Safety
• Nutrition after WLS
• Information Session and Support Group Details
• Webinar on Weight Loss Surgery
• Helpful Links
• Leslie's Story
• Weight Loss and Well-Being E-Letter: Spring 2013

What is BMI?

Surgical treatment for obesity is not for everyone who is overweight.  It is usually reserved for people who have so-called "severe obesity."

We use a tool called body mass index (BMI) to measure the level of obesity.

What does the BMI number mean?

The BMI takes both height and weight into account, so it gives a more accurate picture of body size than weight alone. In general, we use the following categories of BMI when we talk about body weight:

• Underweight = BMI less than 18.5
• Normal weight = BMI between 18.5 and 24.9
• Overweight = BMI between 25 and 29.9
• Obesity = BMI of 30 or greater
  • Class I Obesity = BMI 30-35
  • Class II Obesity = BMI 35-40
  • Class III Obesity = BMI greater than 40

In our program, we use the BMI to help us decide if someone might benefit from weight loss surgery. The surgery is not usually performed on someone with a BMI of less than 40, though there are important exceptions. For example, if there are serious medical problems related to weight, the surgery may be considered in someone with a BMI between 35 and 40. (The surgery is not done on anyone whose BMI is less than 35.)

What is my BMI?

If you'd like a precise measure of your BMI, go to the  NIH website and use the BMI calculator on line.

To use the chart below:
Find your height, in inches, in the left column. Move across and find a weight closest to your own. If your weight is lower than all the values shown next to your height, your BMI is less than 35. If you find a weight close to yours in the row next to your height, the number at the top of that column is your BMI.

Examples:

Someone who is 66 inches tall and weighs 309 pounds has a BMI of 50.

Someone who is 72 inches tall and weighs 250 pounds has a BMI of less than 35.

BMI chart, for BMI 35-54

Or use this formula to calculate your own BMI:

BMI = weight in pounds x 705/height in inches squared

1. What is your weight in pounds? Write your answer ____________

2. Multiply your answer in #1 by 705. Write your answer ___________

3. What is your height in inches? Write your answer __________

4. Multiply the answer in #3 by itself. Write your answer ____________

5. Divide the answer in #2 by the answer in #4. This is your BMI.