For many years, doctors and researchers used insurance statistics to determine what people should weigh. Today, we have a better approach that takes into account the health risks of being overweight. It’s called the Body Mass Index (or BMI), and like your cholesterol and blood pressure, it’s an important number to understand. A higher BMI increases the risk of weight-related health problems.
BMI is a measure which takes into account a person’s weight and height to gauge total body fat in adults. Someone with a BMI of 26 to 27 is about 20 percent overweight, which is generally believed to carry moderate health risks. A BMI of 30 and higher is considered obese. The higher the BMI, the greater the risk of developing additional health problems.
A healthy weight is considered to be a BMI of 24 or less. A BMI of 25 to 29.9 is considered overweight. A BMI of 30 and above is considered obese. Individuals who fall into the BMI range of 25 to 34.9, and have a waist size of over 40 inches for men and 35 inches for women, are considered to be at especially high risk for health problems.
Use the BMI Calculator below to figure your BMI.
FAQs
BMI has been criticized as being an inaccurate tool. One reason is that a person with lots of muscle and minimal body fat can have the same BMI as a person with obesity who has much less muscle.
How do you calculate BMI with solutions? ›
The formula is BMI = kg/m2 where kg is a person's weight in kilograms and m2 is their height in metres squared. A BMI of 25.0 or more is overweight, while the healthy range is 18.5 to 24.9.
Why does my BMI say I'm overweight when I'm not? ›
Your BMI doesn't reveal anything about the makeup of your body, such as how much muscle vs. fat you have. That's why conclusions based only on this number can be misleading, especially when it comes to the following: How muscular you are: A few people have high BMIs but don't have much body fat.
What is better than the BMI calculator? ›
Waist-to-hip ratio may be a better tool for determining weight management than body mass index (BMI), according to a new study .
Can BMI calculators be wrong? ›
An example of the biggest flaw in using BMI
Muscle weighs more than fat (it is denser, a cubic inch of muscle weighs more than a cubic inch of fat). Therefore, BMI will inevitably class muscly, athletic people as fatter than they really are.
Is BMI 100% accurate? ›
According to the new study, BMI misses a lot of cases of obesity. Researchers looked at data from almost 10,000 U.S. adults collected from 2011 to 2018 and found that almost 36% had obesity based on their BMI. Use of a different measure of obesity — a person's body fat percentage — put that figure at 74%.
What is the easiest way to calculate BMI? ›
For men and women over the age of 20, BMI is calculated using a simple formula. First, you will need your height, in inches, and your body weight. Once you have these two factors, you will plug the numbers into a simple formula. The formula for BMI is: weight divided by height squared, times 703.
What is the simple math for BMI? ›
For example the height index for a person 5' 10” tall will be 7 = [5 + (10 / 5)]. Now dividing the weight in pounds by this index will provide a quick estimate for BMI in kg/m2; for example, if the person weighs 210 pounds, and is 5' 10” tall, BMI can be easily calculated by dividing 210 by 7: about 30 kg/m2.
What is the formula for calculating BMI one word answer? ›
Formula used by doctor for BMI: =mh2 where: m is the mass in kilograms and h is the height in metres.
Why is my BMI 25 but I'm not fat? ›
Healthy individuals with BMIs of 25 to 27 aren't always overweight. This is because the “excess” weight may actually not be fat. For instance, very fit athletes often have elevated BMIs.
Adult Body Mass Index
If your BMI is less than 18.5, it falls within the underweight range. If your BMI is 18.5 to <25, it falls within the healthy weight range. If your BMI is 25.0 to <30, it falls within the overweight range. If your BMI is 30.0 or higher, it falls within the obesity range.
Why am I so skinny but heavy? ›
Since dense muscle tissue takes up less space than fat, it's possible you may weigh the same (or even more) yet appear slimmer than another person with the same weight, a similar height and frame because of the difference in your body composition.”
What is the most attractive BMI range? ›
These studies have found that a low waist to hip ratio (WHR) of approximately 0.7 [9] and a low Body Mass Index (BMI; weight scaled for height) of approximately 18–19 kg/m2 [10] are perceived as most attractive in female bodies, while a low waist to chest ratio (WCR) of approximately 0.7, and relatively high BMI ( ...
What is the most accurate BMI test? ›
Dual-energy X-ray absorptiometry (DEXA/DXA) scan.
What is the most accurate BMI equation? ›
Formula: weight (lb) / [height (in)]2 x 703
Then, calculate BMI by dividing weight in pounds (lb) by height in inches (in) squared and multiplying by a conversion factor of 703.
How accurate is BMI percentage? ›
Despite the good correlation between BMI and BF %, the diagnostic accuracy of BMI to diagnose obesity is limited, particularly for individuals in the intermediate BMI ranges. A BMI cut-off of ≥ 30 kg/m2 has a good specificity but misses more than half of people with excess fat.
What is more realistic than BMI? ›
A new study suggests waist-to-hip ratio (WHR) may be a more accurate indicator of health and risk of illness than BMI or body mass index. In the study, a lower WHR was associated with overall better health outcome. Experts explain the differences between BMI and WHR including how to measure at home.
How accurate is BMI if you are muscular? ›
Because BMI utilizes only body weight and height and does not take into account overall body composition, including body fat, muscular individuals may be classified as obese.
Can BMI overestimate body fat? ›
Muscle and bone are denser than fat, so BMI can overestimate body fat in athletes with high bone density and muscle mass or underestimate it in older people who have low bone density and muscle mass.
