decorational arrow Tools   decorational arrow Self-assessment   decorational arrow Obesity Care | 5 min. read

What’s your Body Mass Index (BMI)?*

Your Body Mass Index (BMI) is a number calculated from your weight and height. It’s not a precise calculation of percentage of body fat, but it is an easy way to determine where your weight falls in the range from healthy to unhealthy.

You can use your BMI as a starting point for talking with your doctor about your weight, health and treatment options.

It is important to note that BMI is a useful measurement for most people over 18 years old. But it is only an estimate as it doesn’t take into account age, ethnicity, gender and body composition.

Calculate your BMI

cm
ft
in
kg
st
lb

Your BMI:

__

Your weight classification:

__

Underweight

Being underweight could be a sign you're not eating enough or that you may be ill. If you're underweight, contact your general practitioner for further evaluation.

Normal weight

The medical community recommends that you keep your weight within this range.

Pre-obesity

 * The term ‘pre-obesity’ was previously classified as ‘overweight’ by the World Health Organization (WHO)

People who fall into this category may be at risk of developing obesity. They might also be at risk of developing other health problems, or that their current health problems may worsen. The recommendation is to consult a healthcare provider trained in obesity management.

There are two recommendations for people who fall into the pre-obesity category, which are recommended by European and American clinical guidelines for obesity management in adults.

The recommendation for people with a BMI of between 25.0 and 29.9 and who do not have weight-related health problems (i.e. high blood pressure or high cholesterol) is to prevent further weight gain through healthy eating and increased physical activity.

For people with a BMI of between 27 and 29.0, and who also have weight-related health problems, the recommendation is to lose weight by combining lifestyle interventions and anti-obesity medications to achieve weight loss and improve health and quality of life.

Obesity I

People who have BMI equal or over 30 may have obesity, which is defined as an abnormal or excessive accumulation of fat that may harm health. Today a number of health organisations recognise obesity as a chronic, but manageable disease.

World Health Organisation and other health organisations distinguish three classes of obesity:

 Obesity Classification

 BMI

 Class I

 30.0–34.9

 Class II

 35.0–39.9

 Class III

 Above 40

The BMI ranges are based on the effect excessive body fat has on individual’s health, life expectancy and risk of developing diseases; as BMI increases, so does the risk for some diseases.  

It is recommended that people with a BMI equal or above 30 consult a healthcare provider trained in obesity management for diagnosis, risk assessment and treatment of obesity and weight-related health complications.

The goal of managing and treating obesity is not simply to lose weight, but instead to improve health and lower the risks of other health complications. Losing even a modest amount of weight, such as five percent of body weight or more, and maintaining this weight loss, can improve overall wellbeing, while also reducing the risk of weight-related complications.

There is a range of scientifically proven treatment options for obesity that may be recommended depending on individual needs, health status and the presence or absence of weight-related complications. Treatment may include a combination of the following options**:

* Bariatric surgery is generally considered for people with a BMI of over 35 who also have weight-related complications. It is also generally considered for people with a BMI of 40 or above.

** Disclaimer: This information is not a substitute for the advice of a healthcare provider. If you have any questions regarding your health, you should contact your general practitioner or another qualified healthcare provider.

Obesity II

People who have BMI equal or over 30 may have obesity, which is defined as an abnormal or excessive accumulation of fat that may harm health. Today a number of health organisations recognise obesity as a chronic, but manageable disease.

World Health Organisation and other health organisations distinguish three classes of obesity:

 Obesity Classification

 BMI

 Class I

 30.0–34.9

 Class II

 35.0–39.9

 Class III

 Above 40

The BMI ranges are based on the effect excessive body fat has on individual’s health, life expectancy and risk of developing diseases; as BMI increases, so does the risk for some diseases.  

It is recommended that people with a BMI equal or above 30 consult a healthcare provider trained in obesity management for diagnosis, risk assessment and treatment of obesity and weight-related health complications.

The goal of managing and treating obesity is not simply to lose weight, but instead to improve health and lower the risks of other health complications. Losing even a modest amount of weight, such as five percent of body weight or more, and maintaining this weight loss, can improve overall wellbeing, while also reducing the risk of weight-related complications.

There is a range of scientifically proven treatment options for obesity that may be recommended depending on individual needs, health status and the presence or absence of weight-related complications. Treatment may include a combination of the following options**:

* Bariatric surgery is generally considered for people with a BMI of over 35 who also have weight-related complications. It is also generally considered for people with a BMI of 40 or above.

** Disclaimer: This information is not a substitute for the advice of a healthcare provider. If you have any questions regarding your health, you should contact your general practitioner or another qualified healthcare provider.

Obesity III

People who have BMI equal or over 30 may have obesity, which is defined as an abnormal or excessive accumulation of fat that may harm health. Today a number of health organisations recognise obesity as a chronic, but manageable disease.

World Health Organisation and other health organisations distinguish three classes of obesity:

 Obesity Classification

 BMI

 Class I

 30.0–34.9

 Class II

 35.0–39.9

 Class III

 Above 40

The BMI ranges are based on the effect excessive body fat has on individual’s health, life expectancy and risk of developing diseases; as BMI increases, so does the risk for some diseases.  

It is recommended that people with a BMI equal or above 30 consult a healthcare provider trained in obesity management for diagnosis, risk assessment and treatment of obesity and weight-related health complications.

The goal of managing and treating obesity is not simply to lose weight, but instead to improve health and lower the risks of other health complications. Losing even a modest amount of weight, such as five percent of body weight or more, and maintaining this weight loss, can improve overall wellbeing, while also reducing the risk of weight-related complications.

There is a range of scientifically proven treatment options for obesity that may be recommended depending on individual needs, health status and the presence or absence of weight-related complications. Treatment may include a combination of the following options**:

* Bariatric surgery is generally considered for people with a BMI of over 35 who also have weight-related complications. It is also generally considered for people with a BMI of 40 or above.

** Disclaimer: This information is not a substitute for the advice of a healthcare provider. If you have any questions regarding your health, you should contact your general practitioner or another qualified healthcare provider.

References
  • World Health Organization. Obesity and overweight. Fact sheet 2018 : https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight [Accessed July 2019].
  • Bray G et al. Obesity: a chronic relapsing progressive disease process. A position statement of the World Obesity Federation. Obesity Reviews 2017; 18:715–723.
  • U.S. Department of Health and Human Services Food and Drug Administration Center for Drug Evaluation and Research (CDER). Guidance for Industry Developing Products for Weight Management 2007.
  • Obesity Canada. Obesity in Canada. https://obesitycanada.ca/obesity-in-Canada/ [Accessed July 2019].
  • EASO. Milan Declaration: A Call to Action On Obesity. https://easo.org/2015-milan-declaration-a-call-to-action-on-obesity/ [Accessed July 2019].
  • American Medical Association. Annual Meeting: Resolutions 2012.
  • World Health Organization. Body mass index - BMI: http://www.euro.who.int/en/health-topics/disease-prevention/nutrition/a-healthy-lifestyle/body-mass-index-bmi [Accessed July 2019].
  • Wadden TA et al. Intensive Behavioral Therapy for Obesity Combined with Liraglutide 3.0 mg: A Randomized Controlled Trial. Obesity 2019; 27:75-86.
  • World Health Organization. Body mass index - BMI: http://www.euro.who.int/en/health-topics/disease-prevention/nutrition/a-healthy-lifestyle/body-mass-index-bmi [Accessed July 2019].
  • National Health and Medical Research Council. Clinical practice guidelines for the management of overweight and obesity in adults, adolescents and children in Australia 2013.
  • Yumuk V et al. European Guidelines for Obesity Management in Adults. Obesity Facts 2015; 8:402-424.

Related articles