Adolescents have grown taller and put on weight over the last thirty years, but the problem of underweight teens may be worse, a study in the online open access journal BMC Public Health suggests.
An analysis of the height, weight, and body-mass index of teenagers during 1966-1969 and 1995-1997 in Norway demonstrates a shift towards taller and heavier teenagers, but also hints that there are more underweight adolescents.
Health researchers commonly use body mass index (BMI), calculated as weight in kilograms divided by the height in meters squared, in weight-related health studies. Sigrid Bjørnelv of the Norwegian University of Science and Technology and colleagues write that changes in these measurements across society over periods of time often reflect changes in nutrition.