Updated

The nation's waistline is expanding, and so too is the role of obesity in child custody battles in the US.

Family-law practitioners and legal experts say mothers and fathers in custody lawsuits are increasingly hurling accusations at each other about the nutrition and obesity of their children, largely in attempts to persuade judges that their kids are getting less-than-optimal care in the hands of ex- and soon-to-be-ex-spouses.

The evidence used to support the allegations varies. In some cases, it Is a grossly overweight child. In others, it is evidence that soft drinks and potato chips make up a disproportionate part of a child's diet. In still others, it is that the other parent is too obese to perform basic child-rearing functions.

"It's come up quite a bit in the last couple of years," said Douglas Gardner, a family-law practitioner in Tempe, Ariz. "Typically, one parent is accusing the other of putting a child at risk of developing diabetes or heart disease—or saying that the child is miserable because he's getting made fun of at school."

For judges in many states, the question of custody turns largely on one question: What is in the best interest of the child? Some states such as Pennsylvania recently altered their definition so that the criteria now clearly include the physical as well as the emotional well-being of the child.

Vincent Bernabei Jr., a family-law attorney in Portland, Ore., had a case recently in which the child's diet was "basically fast-food restaurants morning, noon and evening," and his weight was in the 95th percentile for his age. Further investigation found the child also was not getting proper medical care, his vaccines were not up to date, and he was having trouble at school. The judge made the decision to switch custody.

The case was "a stew of issues, and the obesity was one," said Bernabei.

The issue is surfacing more often partly because obesity numbers have risen and the public is becoming more aware of the health dangers related to being overweight, according to lawyers surveyed by TotalAttorneys.com, an attorney-referral service. According to the Centers for Disease Control and Prevention, approximately 17 percent, or about 12.5 million, of the nation's children and teens are obese. Since 1980, according to CDC statistics, obesity rates have nearly tripled.

"It used to be constantly and consistently about smoking," said Jeff Wittenbrink, a family-law specialist in Baton Rouge, La. "It's only been recently where one parent thinks their kid's not active enough, is gaining weight and eating sugary food."

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