Body mass index, weight and height in children and adolescents
The World Health Organisation has developed growth curves for children aged 0-5 years. IOTF curves are used to assess body mass index, weight and height in children and adolescents between 2 and 18 years. These are also known as the Cole index.
Weight and height for children 0-5 years
In 2006, WHO published new growth curves for children aged 0-5 years old. They are based on 8,000 healthy breast-fed children from six countries, including children from Oslo.
The curves provide information about the normal height and weight development of healthy children who have grown up under optimal conditions, and who were only breastfed as babies.
For the first time the growth curves give a standard for body mass index (BMI) for children between one and five years old. In addition, a standard has been published for motor development, for example, when a child should be able to sit, stand and walk.
Weight and height in children 5-18 years
For children and young people between 5 and 18 years, there is no good international benchmark. One can refer to older Norwegian tables for height and weight or to more recent Swedish tables.
One can also use IOTF’s (International Obesity Task Force) index for overweight and obesity, (Cole index). These curves define what can be regarded as overweight and obesity in girls and boys of different ages between 2 and 18 years. The index was published in 2000, based on data from 180,000 children in Brazil, UK, Hong Kong, Netherlands, Singapore and the USA. The data foundation is somewhat more uncertain than the basis for the WHO curves.
In 2007, Cole and colleagues published a new report, this time using curves to assess what is classed as underweight in children and adolescents. Like the BMI for overweight, BMI for underweight varies with age and gender. Over 18 years of age, a BMI below 18.5, 17 and 16 kg/m2 will be classified as being underweight grade I, II and III respectively.