Body Mass Index, or BMI, is a tool physicians and researchers use to quickly identify individuals who suffer from obesity or near obesity.
BMI can be calculated using the same formula for all individuals, but the numbers have a different meaning for adults, teens, and children, and differ by gender. To account for the difference, the Centers for Disease Control and Prevention (CDC) has created specific growth charts that vary for children and by gender. The charts then use a percentile based on these specific data.
Underweight: below the 5th percentile
Normal Weight: 5th percentile to below than the 85th percentile
Overweight: 85th percentile to below than the 95th percentile
Obese: 95th percentile or higher
The chart below shows you the basic BMI chart for individuals. Find your height and then find your weight to see your BMI.
BMI below 18.5 = underweight
BMI between 18.5 and 24.9 = healthy or healthy weight
BMI of between 25 and 29.9 = overweight
BMI of 30 and above = obese.
Why is BMI so important?
First it provides a quick, easy way to examine your risk for certain diseases and health issues. Most notably, a higher BMI puts you at risk of certain types of cancers, hypertension, and coronary heart disease.
People who are obese are at increased risk for many diseases and health conditions, including the following:
- High blood pressure (hypertension)
- High LDL cholesterol, low HDL cholesterol, or high levels of triglycerides (dyslipidemia)
- Type 2 diabetes
- Coronary heart disease
- Gallbladder disease
- Osteoarthritis (a breakdown of cartilage and bone within a joint)
- Sleep apnea and breathing problems
- Chronic inflammation and increased oxidative stress
- Some cancers (endometrial, breast, colon, kidney, gallbladder, and liver)
- Low quality of life
- Mental illness such as clinical depression, anxiety, and other psychiatric disorders
- Body pain and difficulty with physical functioning
Although BMI is a great way to determine your health risks, it isn’t perfect. BMI calculation tends to overstate risks for men and understates risks for women. Simply put, men typically have more muscle mass than women, giving them a higher BMI. Likewise, anybody with more or less muscle mass than the average person will experience less accurate BMI results.
It’s important to measure yourself regularly to ensure that you’re not approaching the threshold of obesity. You should measure yourself at least monthly to establish a baseline, and to make sure you’re in the healthy range. Even staying in the healthy BMI range can reduce your health insurance costs.
Sometimes those who measure themselves may be surprised or even shocked at their BMI, finding out they are classified as overweight or obese. This classification is beneficial even to those who ”feel” healthy, because the science says, almost unequivocally, that those in the obese classification have increased health risks.
The following infographic shares what your BMI says about your health.
John Wright is a health writer and outreacher at re:new Bariatrics, a consumer’s guide to obesity treatments and bariatric surgery. Renew Bariatrics is a weight-loss surgery guide for patients looking at options to conquer obesity. John keeps up with all the latest health news, enjoys coffee before anything else, and occasionally reviews roller coasters.