Body mass index

Body Mass Index (BMI)

According to the WHO, body mass index (BMI) is a tool that allows you to assess your overall degree of obesity. It shows, depending on your size, the weight range associated with the risks to health.

BMI (kg / m 2 ) is calculated from weight (in kg) divided by height (in m) squared. BMI = weight (kg) / height (m 2 ). The international overweight criterion is a BMI of 25, while that of obesity is a BMI greater than 30

Calculation of body mass index (BMI)

Metric Imperial
Cut cm Cut ft in
Weight kg Weight lb


  • Healthy weight ( BMI> 18.5)
  • Overweight ( BMI> 25)
  • Obesity class 1 ( BMI> 30)
  • Obesity class 2 ( BMI> 35)
  • Obesity class 3 ( BMI> 40) or massive obesity (morbid)

Classification based on body mass index

(Reference: International Obesity Task Force   (IOTF) )

Categories BMI (kg / m 2 ) * Risks of co-morbidities
Under the normal <18.5 Low (but greater risk for other clinical problems including mortality)
Normal extent 18.5-24.9 low
overweight 25.0-29.9 Some risks
Obese > 30.0
Class I 30.0-34.9 high
Class II 35.0-39.9 Very high
Obese morbid
Class III > 40.0 Extremely high

* Note: These values are independent of age and sex and correspond to the same level of adipose tissue from one population to another.

** Note: It is important to measure BMI and body fat distribution (waist circumference or hip-hip circumference ratio, etc.) to assess the risk of co-morbidities of obesity. An insufficient BMI <18.5 kg / m 2 represents a greater risk of developing other clinical problems. Free quote

Measure your waistline

Waist circumference is a marker of adiposity complementary to that of BMI. Measuring the waist circumference (abdomen circumference) allows, using a tape measure, to identify excess fat in the abdomen. When waist circumference is greater than 88 cm in women or 102 cm in men , it is considered that there is abdominal obesity. Abdominal obesity is associated with an increased risk of diabetes, hypertension, hypertriglyceridemia, and vascular disease.

Desirable Increased risk High risk
Wife Man Wife Man Wife Man
<80cm <94cm > 80cm > 94cm > 88cm > 102cm
<32 “ <37 “ > 32 “ > 37 “ > 35 “ > 40 “

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