Teenage girls who feel depressed are twice as likely to start binge eating as compared to their counterparts, a new study has found.
According to the new nationwide study, the reverse is also true, as, girls who engage in regular binge eating have double the normal risk of symptoms of depression.
The study, conducted by Alison Field and his team of researchers from Harvard Medical School and Harvard School of Public Health, is the largest to look at the relationship between binge eating and depression during adolescence, when most eating disorders surface.
The study authors defined binge eating as eating a large amount of food in a short amount of time and feeling a lack of control over eating during the episode. It also labelled girls who ate large amounts of food but did not feel out of control "overeaters".
The findings of the study rely on surveys conducted as part of the nationwide Growing Up Today Study. The authors focused on girls because eating disorders and depression are more common in females than in males.
The researchers analysed data from nearly 5,000 girls aged 12 to 18 who answered questions in 1999, with follow-up surveys in 2001 and 2003.
Teens and young women who reported in the first survey that they always or usually felt "down in the dumps" or "depressed" were about twice as likely as others were to start overeating or binge eating during the following two years.
"The most common approach to obesity has been to focus on eating better and exercising more, but many pathways can lead to being overweight," Marian Tanofsky-Kraff, a clinical psychologist at the Uniformed Services University of the Health Sciences in Maryland, said.
"There is a group of people where it may be more psychologically driven. Targeting some of these psychological factors might help prevent obesity," Tanofsky-Kraff added.
The authors note that the survey respondents included few youths belonging to ethnic minorities or lower socioeconomic groups, so the study findings might not apply to all populations. In addition, the surveys did not include information on use of medications, such as antidepressants, which might affect outcomes.
The study has been published in current issue of the Journal of Adolescent Health.