About the growth study

Updated knowledge of growth and weight development is important for all health-related work with children and adolescents, due to follow up of the child, but also to monitor trends in the child population.Children’s growth and development depends on heredity and environment. Norwegian children have gradually grown taller over the last hundred years, which reflects amongst other things, better well-being, improved nutrition and fewer infections. In the last 20-30 years weight in older children and adults has also increased.


The Bergen growth study is a research project that was started in 2003 and which, amongst other things, aims to identify and describe the growth and weight development of Norwegian children. Data has been collected from more than 8000 children aged 0-19 years who where measured at the Health clinics, kindergartens and schools in Bergen. You can read more about the research project here.

Growth curves:

In the winter of 2007-2008 new growth curves was made for Norwegian children aged 0-19 years based on data from the growth study in Bergen and the Medical Birth Registry. Norwegian school children are taller today than the previous growth references show. Weight for height has also increased. You can read more about the curves and download them here.

The Bergen Growth Study 2:

The first childhood growth study (Vekststudien i Bergen 1) was conducted between the years 2003 and 2006, which made it possible to develop growth charts in use throughout the country since then. We are now conducting a follow-up study that aims to investigate the development of puberty among Norwegian children, The Bergen Growth Study 2. Our knowledge of puberty in Norwegian children is limited. In other countries, such as Denmark and the United States, researchers are seeing indications that children reach puberty earlier than before. It is unclear why this is happening. Children may be reaching puberty earlier due to altered body composition (increased fat tissue) or because they are absorbing substances that influence this development (so-called endocrine disruptors). Early puberty has its downsides; it can increase the risk of obesity, have negative psycho-social implications and some studies have associated early puberty with certain forms of cancer. The purpose of our study is to document normal range of puberty among Norwegian children by measuring growth, mapping development, analysing hormones in blood and saliva, and identify the genes that are involved. We wish to provide objective measurements of this development by taking into use ultrasound. Furthermore, we want to examine factors that may influence development by measuring body composition and the occurrence of endogenic disruptors in the body.

This study involves measuring height, weight and waist circumference. All measurements are done at the child’s school. Furthermore, for the girls, a female nurse measures the size of the mammary glands by using ultrasound. For the boys, a male radiographer measures the size of the testicles, also by using ultrasound. The development of pubic hair will also be registered. The child’s body is covered so he/she will not feel exposed. The children are usually not required to take off their underwear or singlets. The examination is done individually and the child kept separate from the others during the examination. Body composition is measured by using a method called bioimpedance. Bioimpedance equipment measures quantities of muscle, bone and fat in the body. Blood and saliva samples are taken after that. The examination takes very little time and is painless (taking blood entails a minor prick, but if your child wishes we can spray the skin with an anaesthetic spray). We are also asking the parents to fill out a questionnaire. The data collection started in early January 2016 and will continue until summer.

Every child who participates in the study will receive a free cinema ticket and a diploma that states their current height!