Children who have poor emotional relationships with their mothers are more than twice as likely to become obese, according to a U.S. study.

Researchers found that the lower the quality of the relationship between mothers and children during their toddler years, the higher the risk that a child would be obese at age 15.

Among those toddlers who had the lowest-quality emotional relationships with their mothers, more than a quarter were obese as teens, compared to 13 percent of those who had closer bonds with their mothers.

Researchers from Ohio State College of Public Health, Columbus, and Temple University, Pa., discovered the trend after analyzing data about mother-child relationships from 977 people who took part in a national study on child care.

That study involved researchers monitoring children born in 1991 interacting with their mothers at age 15, 24 and 36 months to see how supportive the mothers were, and how secure their children felt.

The authors of the new study believe children who feel insecure as toddlers are more likely to become obese as they are less able to deal with stress, causing them to comfort eat and sleep less.

"Sensitive parenting increases the likelihood that a child will have a secure pattern of attachment and develop a healthy response to stress," lead author Sarah Anderson said. "A well-regulated stress response could in turn influence how well children sleep and whether they eat in response to emotional distress -- just two factors that affect the likelihood for obesity."

The study will be published in the January issue of the journal Pediatrics.