Healthy-weight girls who think they are fat are more likely to be depressed than fatter girls who realise they are overweight. Researchers from Penn State University studied 12,683 adolescents taking part in the National Longitudinal Study of Adolescent Health. The children were asked about their actual weight, whether they thought they were over-, under- or the right weight and their levels of depression were assessed. 80% of the girls were overweight knew they were too fat whereas 40% of the overweight boys thought that they were at a healthy weight. The girls who thought they were overweight but were actually at a healthy weight were more depressed than girls who were overweight and knew they were. Boys who were actually underweight were more likely to be depressed than boys who were heavier with the researchers describing them as 'extremely distressed.'