Dr. David Ludwig, an obesity specialist at Harvard-affiliated Children's Hospital Boston, said the point isn't to blame parents, but rather to act in children's best interest and get them help that for whatever reason their parents can't provide.
State intervention "ideally will support not just the child but the whole family, with the goal of reuniting child and family as soon as possible. That may require instruction on parenting," said Ludwig, who wrote the article with Lindsey Murtagh, a lawyer and a researcher at Harvard's School of Public Health.
"Despite the discomfort posed by state intervention, it may sometimes be necessary to protect a child," Murtagh said.
But University of Pennsylvania bioethicist Art Caplan said he worries that the debate risks putting too much blame on parents. Obese children are victims of advertising, marketing, peer pressure and bullying -- things a parent can't control, he said.
"If you're going to change a child's weight, you're going to have to change all of them," Caplan said.
Roughly 2 million U.S. children are extremely obese. Most are not in imminent danger, Ludwig said. But some have obesity-related conditions such as Type 2 diabetes, breathing difficulties and liver problems that could kill them by age 30. It is these kids for whom state intervention, including education, parent training, and temporary protective custody in the most extreme cases, should be considered, Ludwig said.
While some doctors promote weight-loss surgery for severely obese teens, Ludwig said it hasn't been used for very long in adolescents and can have serious, sometimes life-threatening complications.
"We don't know the long-term safety and effectiveness of these procedures done at an early age," he said.
Ludwig said he starting thinking about the issue after a 90-pound 3-year-old girl came to his obesity clinic several years ago. Her parents had physical disabilities, little money and difficulty controlling her weight. Last year, at age 12, she weighed 400 pounds and had developed diabetes, cholesterol problems, high blood pressure and sleep apnea.
"Out of medical concern, the state placed this girl in foster care, where she simply received three balanced meals a day and a snack or two and moderate physical activity," he said. After a year, she lost 130 pounds. Though she is still obese, her diabetes and apnea disappeared; she remains in foster care, he said.
In a commentary in the medical journal BMJ last year, London pediatrician Dr. Russell Viner and colleagues said obesity was a factor in several child protection cases in Britain. They argued that child protection services should be considered if parents are neglectful or actively reject efforts to control an extremely obese child's weight.
A 2009 opinion article in Pediatrics made similar arguments. Its authors said temporary removal from the home would be warranted "when all reasonable alternative options have been exhausted."
That piece discussed a 440-pound 16-year-old girl who developed breathing problems from excess weight and nearly died at a University of Wisconsin hospital. Doctors discussed whether to report her family for neglect. But they didn't need to, because her medical crisis "was a wake-up call" for her family, and the girl ended up losing about 100 pounds, said co-author Dr. Norman Fost, a medical ethicist at the university's Madison campus.
State intervention in obesity "doesn't necessarily involve new legal requirements," Ludwig said. Health care providers are required to report children who are at immediate risk, and that can be for a variety of reasons, including neglect, abuse and what doctors call "failure to thrive." That's when children are severely underweight.
Jerri Gray, a Greenville, S.C., single mother who lost custody of her 555-pound 14-year-old son two years ago, said authorities don't understand the challenges families may face in trying to control their kids' weight.
"I was always working two jobs so we wouldn't end up living in ghettos," Gray said. She said she often didn't have time to cook, so she would buy her son fast food. She said she asked doctors for help for her son's big appetite but was accused of neglect.
Her sister has custody of the boy, now 16. The sister has the money to help him with a special diet and exercise, and the boy has lost more than 200 pounds, Gray said.
"Even though good has come out of this as far as him losing weight, he told me just last week, `Mommy, I want to be back with you so bad.' They've done damage by pulling us apart," Gray said.
Stormy Bradley, an Atlanta mother whose overweight 14-year-old daughter is participating in a Georgia advocacy group's "Stop Childhood Obesity" campaign, said she sympathizes with families facing legal action because of their kids' weight.
Healthier food often costs more, and trying to monitor kids' weight can be difficult, especially when they reach their teens and shun parental control, Bradley said. But taking youngsters away from their parents "definitely seems too extreme," she said.
Dr. Lainie Ross, a medical ethicist at the University of Chicago, said: "There's a stigma with state intervention. We just have to do it with caution and humility and make sure we really can say that our interventions are going to do more good than harm."