Unhappy Families Can Make Daughters Fat

Childhood obesity has become such a big problem in the United States that the rate of obese adolescents—21%—exceeds the rate of overweight adolescents (14%). It’s been that way for the last decade.

Dr. Daphne Hernandez, assistant professor at the University of Houston, wants to figure out why despite our efforts, that rate hasn’t budged. “Many times when we’re designing interventions and prevention programs, they’re done in schools because that’s where we have ease of access to all these kiddos,” she says. “But the issue is that in those interventions, we don’t think about the family environment and what could be happening at home.”

In her new study published in the journal Preventive Medicine, she decided to look at three family stressors: family disruption and conflict, the kind a kid would experience after a parent got divorced, remarried, incarcerated or if the child experienced a violent crime or death of a loved one; financial stress, a measure of poverty determined in part by whether a mom was unemployed or had less than a high school education; and maternal poor health, whether the mom was a binge drinker, drug user or had elevated depression.

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Hernandez analyzed data from 4,762 adolescents between 1975-1990 using the National Longitudinal Study of Youth. She measured each adolescent’s exposure to these family factors from birth until age 15, then looked at their weight at age 18. The results showed clear gender differences. In adolescent girls, experiencing family disruption and financial stress repeatedly was linked to overweight or obesity by age 18. That wasn’t true for adolescent boys. Just one stress point—poor maternal health—was linked to being overweight or obese by 18.

When all the findings were lumped together, Hernandez says, the gender differences disappeared. “Not all stress influences females and males the same,” she says. The reason why lies beyond the scope of this study, but Hernandez suspects it has something to do with physiolgocial and behavioral stress responses. Your body secretes cortisol when it’s stressed, she says—which, if chronic, suppresses your body’s ability to feel satiated. “Behaviorally, you then gravitate more towards the more palatable foods, the high calorie, high fat foods, so you’re not reaching for that apple or celery stick,” she says. This pattern seems to be more prevalent in females than in males, she adds.

“We really need to think about how we are teaching our adolescents how to deal with stress, and trying not to use food as a way to deal with stress,” Hernandez says. “Perhaps encouraging physical activity is the way we should be going.”

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