Overweight definition using Body Mass Index
Calculate your BMI here with our very own Body Mass Index calculator. This calculator uses the BMI formula, that is your weight in kilograms divided by your height in metres squared. Don’t worry about the math the calculator does it all for you!
The standard Overweight Definition
- For adults, a Body Mass Index (BMI) of 25 or more is considered overweight and a BMI of 30 or more is considered obese.
- For children, the charts of Body-Mass-Index for Age are used, whereby a BMI greater than the 85th percentile is considered at risk of becoming overweight. Furthermore, a BMI greater than the 95th percentile is considered obese.
Combined, the Child and Adult criteria form a chart like this below:-
… and here is the Obesity criteria:-
Click on the links below to see the boys or girls BMI charts in more detail:-
Is there room for improvement of these standard definitions?
Naturally yes, and here are 5 reasons why:-
- Body Mass Index changes with Age: Obviously in children but also for adults too.
- Men and Women are different, so why should adult men and women have exactly the same BMI range?
- Short adult women have a higher BMI than taller women.
- Race/ethnicity and nationality affect body composition and BMI.
- Muscular people, athletes and bodybuilders particularly (anybody with a high percentage of muscle mass), have high BMI values, but are not necessarily fat.
Some Background Information and Problems with the Overweight Definition
From the NHANES II survey ( USA 1976-1980 )3, the definitions of ‘Overweight’ and ‘Obesity’ were used until the year 2000. ( You can still use them, if you like.)
|underweight||< 19.1||< 20.7|
|in normal range||19.1 – 25.8||20.7 – 26.4|
|marginally overweight||25.8 – 27.3||26.4 – 27.8|
|overweight||27.3 – 32.3||27.8 – 31.1|
|very overweight or obese||> 32.3||> 31.1|
These NHANES II definitions had several nice features:
- Men and Women had different overweight thresholds. A BMI of around 27.3 for women and 27.8 for men.
- The concept of ‘Marginally overweight’ is a nice sounding phrase. Furthermore, marginally overweight begins at 25.8 for women and 26.4 for men.
This range for the overweight definition (BMI above 25 for men and women) was chosen to be suitable for international standardization. Furthermore, it is simple enough to remember and to calculate with a pencil and paper.
Next, click on the link to read about the halls.md v2 classification of BMI for body description that you may prefer to use instead.
Health Risks of being ‘truly’ overweight or obese
However saying all that, and despite the academic debate for calculating accurate bmi ranges, the National Institute of Health warns that:-
‘… being overweight or obese puts you at risk for many health problems.’
Other surfing choices:
- Return to the Body Mass Index calculator for women,
- Or to the BMI calculator for men, which is more gender neutral,
If you are overweight and would like to get some help on achieving a healthy weight :-
- 6 Reasons why weight loss is not working
- How to lose weight fast
- Motivation for weight loss
- Quick weight loss pills
- Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. National Heart, Lung and Blood Institute. June 17, 1998
- Preventing and Managing the Global Epidemic of Obesity. Report of the World Health Organization Consultation of Obesity. WHO, Geneva, June 1997
- NHANES II. 1976-1980 data from USA.