Medical ethicist Art Caplan was back on Boston Public Radio on Wednesday to tackle a contentious subject: childhood obesity. The CDC recently reported a doubling in obesity for kids six to eleven years old, and a quadrupling in 12-t0-19-year-olds over the last three decades.

In light of that fact, a recent Washington Post article chronicled schools' novel efforts to ward off obesity. One of those has already infiltrated the workplace: standing desks. The Post article quoted Texas A&M University professor Mark Benden.

"Children become more restless and distracted with prolonged sitting. Active workstations reduce disruptive behavior problems and increase students' attention," Benden said.

Art Caplan liked the idea, but said that schools could save themselves a bundle of money bringing back old exercise programs they've scuttled.

"I still think though just putting back recess, having phys-ed return to the schools, have more sports for kids both in elementary, high school, and college, [and for] those who aren't the superstars! We have this weird [thing] where we love sports, but we only apparently love it played by the top 1/1000th percent of people."

A new study showed the importance not only of combating obesity in children, but in all age groups. The American Journal of Public Health reported that more than 99 percent of obese people fail to ever reach and maintain a normal weight. Caplan pointed to yo-yo dieting as proof.

"Each of us can go on a diet right after New Year's, lose five pounds, and feel pretty good about ourselves. It's just that by the time the New Year comes we're six pounds heavier."

Caplan blamed sedentary behavior — unhealthy environmental reinforcement, digital entertainment — for sudden spikes in obesity, but he didn't stop there.

"We're pushing bigger portions and fattier foods."

Caplan said it's time to blow the whistle on this public health crisis.

"This is a top priority. [We need] better ideas of how to lose weight," Caplan said. "Right now we don't know what we're doing."

>>Art Caplan is the head of the division of medical ethics at NYU's Langone Medical Center. He's also cohost of the Everyday Ethics podcast. You can hear him every Wednesday on BPR.