Obesity raised anxiety and depression risk by 33% among young boys.
According to the Centers for Disease Control and Prevention (CDC), over 35% of young adults in the United States are obese.
Among U.S. adolescents, mental health conditions are also prevalent.
Louise Lindberg, from the Karolinska Institutet in Stockholm, Sweden, is the lead researcher of the new study.
She and her colleagues presented their findings at the European Congress on Obesity, which this year took place in Glasgow, United Kingdom.
Anxiety, depression risk higher by up to 43%
Lindberg and her team examined data on over 12,000 children and teenagers ages 6–17 who had received treatment for obesity, and they compared them with the data of more than 60,000 counterparts who did not have obesity.
Researchers sourced the data in 2005–2015 as part of the Swedish Childhood Obesity Treatment Register. Over an average period of 4.5 years, more than 4,200 of the children and teenagers developed anxiety or depression.
The girls with obesity were 43% more likely to experience anxiety or depression compared with their age- and sex-matched peers. The risk of anxiety and depression was also 33% higher among boys with obesity, compared with their peers who did not have obesity.
The team adjusted for other risk factors for depression and anxiety, such as migration background, other neuropsychiatric conditions, a history of mental health issues in the family, and socioeconomic status.
After adjusting for these factors, obesity still raised the risk of developing anxiety and depression.
Specifically, 11.6% of the girls who had obesity received such a diagnosis, compared with 6% of girls without obesity. Also, 8% of boys with obesity received the diagnosis, compared with 4.1% of boys without obesity.
“We see a clear increased risk of anxiety and depressive disorders in children and adolescents with obesity compared with a population-based comparison group that cannot be explained by other known risk factors such as socioeconomic status and neuropsychiatric disorders,” explains Lindberg.
“These results suggest that children and adolescents with obesity also have an increased risk of anxiety and depression, something that healthcare professionals need to be vigilant about.”
The scientists also acknowledge some limitations to their study; for example, that it is observational and cannot say anything about the mechanisms behind the associations.
Importantly, they had no access to any information on the height or weight of the boys and girls in the control group.
Finally, the data on how many people have anxiety and depression may be biased. This is because many people who live with these conditions do not seek professional help.
“Given the rise of obesity and impaired mental health in young people,” Lindberg goes on to say, “understanding the links between childhood obesity, depression, and anxiety is vital.”
“Further studies are needed to explain the mechanisms behind the association between obesity and anxiety/depression,” she concludes.