*The following is excerpted from an online article posted on HealthDay.
Starting at age 7, kids can get stuck in a vicious cycle of obesity and emotional problems that is hard to escape, British researchers say.
Investigators are not sure what triggers the struggle, but new study findings suggest that, over time, youngsters who are obese are likely to develop anxiety and moodiness, while those with emotional problems are more apt to become obese.
"Awareness and understanding that higher weight and emotional problems often occur together might be important for parents," said study co-author Charlotte Hardman, a senior lecturer at the University of Liverpool in England. "For health care practitioners working in prevention and early intervention, targeting both health outcomes might be of benefit."
Hardman and co-author Praveetha Patalay tracked the mental health and body mass index (BMI) of more than 17,000 British kids born between 2000 and 2002. (BMI is a measure of body fat based on height and weight.)
Although the researchers found no connection between obesity and emotional issues among very young children, the link was clear by age 7 and strengthened as kids got older.
Kids who were obese at age 7 had a greater risk of emotional difficulties at age 11, which then predicted a high BMI at 14, the study authors found.
"Specifically, higher body mass index and emotional problems tended to occur together in mid-childhood and adolescence, from ages 7 to 14, but not in early childhood at ages 3 and 5," Hardman said.
What's more, 7- to 14-year-old girls had, on average, higher BMI and emotional difficulties than boys.
Still, Hardman noted that boys and girls in that age range were about equally likely to struggle with some degree of obesity and/or mental health difficulties, such as being anxious or in a bad mood.
The team first reported their findings in the March 20 online issue of JAMA Psychiatry, and are scheduled to present their research this week at a meeting of the European Congress on Obesity in Glasgow, Scotland.
For the study, Hardman and Patalay analyzed a nationally representative sample of kids enrolled in the U.K.'s Millennium Cohort Study.
It collected BMI information on participants at 9 months and then five more times at ages 3, 5, 7, 11 and 14. Their parents filled out questionnaires about their children's mental health. The findings were adjusted for factors known to affect both obesity and mental health, including gender, ethnicity, behavior problems and parents' mental health.
Nearly 8% of the kids were clinically obese by age 14. By then, nearly twice as many were struggling with anxiety and feelings characterized as a "bad mood," the study found.
Though poverty played a part in the link between weight and mental health, there was an across-the-board association between BMI and emotional problems. Hardman said that suggests social, physiological and psychological processes become increasingly important as children age.
The study didn't explore underlying reasons and it does not prove cause and effect.