- Body Mass Index (BMI) Center
- Weight Gain Shockers Slideshow Pictures
- Take the Quiz on Belly Fat
- The Best Diet Tips Ever Slideshow Pictures
*BMI facts medical author: Melissa Conrad Stöppler, MD
- BMI stands for body mass index. BMI is calculated by a formula that takes into account both a person's height and weight.
- BMI is reported as weight in kilograms (kg) divided by height in meters squared (m2).
- BMI is useful in classification of obesity, overweight, and healthy weight.
- Obesity is generally defined as a BMI of 30 or greater, while healthy weight for adults refers to a BMI of at least 19 and less than 25.
- A BMI of 40 or more is often used to identify people who are extremely obese and at risk for serious health complications of obesity.
What is BMI?
Body mass index, or BMI, is a new term to most people. However, it is the measurement of choice for many physicians and researchers studying obesity. BMI uses a mathematical formula that takes into account both a person's height and weight. BMI equals a person's weight in kilograms divided by height in meters squared (kg/m2).
What is a healthy weight?
It is important to understand what "healthy weight" means. Healthy weight is defined as a body mass index (BMI) equal to or greater than 19 and less than 25 among all people aged 20 or over. Generally, obesity is defined as a body mass index (BMI) equal to or greater than 30, which approximates 30 pounds of excess weight. Excess weight also places people at risk of developing serious health problems.
BMI chart for weight and height
The table below has already done the math and metric conversions. To use the table, find the appropriate height in the left-hand column. Move across the row to the given weight. The number at the top of the column is the BMI for that height and weight.
|Height (in.)||Weight (lb.)|
Body weight in pounds according to height and body mass index.
Below is a table identifying the risk of associated disease according to BMI and waist size.
|BMI||Category||Waist less than or equal to 40 in. (men) or 35 in. (women)||Waist greater than 40 in. (men) or 35 in. (women)|
|18.5 or less||Underweight||N/A||N/A|
|18.5 - 24.9||Normal||N/A||N/A|
|25.0 - 29.9||Overweight||Increased||High|
|30.0 - 34.9||Obese||High||Very High|
|35.0 - 39.9||Obese||Very High||Very High|
|40 or greater||Extremely Obese||Extremely High||Extremely High|
Quick GuideSurprising Reasons for Weight Gain
Daily Health News
Diet and Weight Loss Resources
Subscribe to MedicineNet's Weight Loss/Healthy Living Newsletter
Portions of the above information has been provided with the kind permission of the Partnership for Healthy Weight Management, www.consumer.gov). Last update May 8, 2007
Top Body Mass Index (BMI) Related Articles
Belly Fat FoodsIs belly fat deadly? What kinds of foods are good and bad for belly fat? Take this quiz to learn about belly fat, how it can be dangerous, and what you can do about it.
Childhood ObesityFast-food consumption and lack of exercise are just a couple of causes of childhood obesity. Health effects of childhood obesity include type 2 diabetes, heart attack, stroke, high cholesterol, asthma, sleep apnea, gallstones, fatty liver disease, GERD, depression, and eating disorders.
Obesity (Weight Loss)Obesity is the state of being well above one's normal weight. A person has traditionally been considered to be obese if they are more than 20% over their ideal weight. That ideal weight must take into account the person's height, age, sex, and build.
Why Does Your Doctor Do That?Your physical exam is when you need your doctor's expert help. Your health depends on it. Learn how doctors spot high blood pressure, STIs, various cancers, and other signs of poor health. What questions should you ask your doctor? Find out here.
Pregnancy: Multiple Births, Twins, Triplets, and MoreMultiple births occur when a woman bears twins, triplets, or even more babies during pregnancy. More multiples are born today thanks to assisted reproductive technology (ART), including in vitro fertilization using fertility drugs. Women carrying multiples often give birth via C-section.