Body mass index (BMI)

Body mass index

The body mass index (BMI) or Quetelet index is a value derived from the mass (weight) and height of an individual. The BMI is defined as the body mass divided by the square of the body height, and is universally expressed in units of kg/m², resulting from mass in kilograms and height in metres.

The WHO regards a BMI of less than 18.5 as underweight and may indicate malnutrition, an eating disorder, or other health problems, while a BMI equal to or greater than 25 is considered overweight and above 30 is considered obese.^[1] These ranges of BMI values are valid only as statistical categories.

Category	BMI (kg/m2)
	from	to
Underweight		18.5
Normal Range	18.5	23
Overweight—At Risk	23	25
Overweight—Moderately Obese	25	30
Overweight—Severely Obese	30

Japan Society for the Study of Obesity (2000):

Category	BMI (kg/m2)
	from	to
Low		18.5
Normal	18.5	25
Obese (Level 1)	25	30
Obese (Level 2)	30	35
Obese (Level 3)	35	40
Obese (Level 4)	40

In Singapore, the BMI cut-off figures were revised in 2005, motivated by studies showing that many Asian populations, including Singaporeans, have higher proportion of body fat and increased risk for cardiovascular diseases and diabetes mellitus, compared with Caucasians at the same BMI. The BMI cut-offs are presented with an emphasis on health risk rather than weight.

Health Risk	BMI (kg/m2)
Risk of developing problems such as nutritional deficiency and osteoporosis	under 18.5
Low Risk (healthy range)	18.5 to 23
Moderate risk of developing heart disease, high blood pressure, stroke, diabetes	23 to 27.5
High risk of developing heart disease, high blood pressure, stroke, diabetes	over 27.5

 https://en.wikipedia.org/wiki/Body_mass_index