When a child is overweight, laying off the sugary snack foods and spending more time on the jungle gym may be good ways to drop a few points. But new research shows that there's another effective weight loss method that you've probably never considered: reading a book.

True, turning a page doesn't burn a ton of calories – but reading can have surprising results on body image, as long as you pick the right book. In a new study from Duke Children's Hospital, a group of obese girls between the ages of 9 and 13 who were part of the hospital's Healthy Lifestyles Program were asked to read a book called Lake Rescue, which featured an overweight protagonist who eventually loses weight. Another group of girls in the same program read a book featuring a thin heroine, while a third control group didn't read a book at all.

After six months, all of the girls who'd read books had lost weight – but the girls who'd read Lake Rescue had lost significantly more weight than the others, reducing their body mass index by .71 percent, as opposed to .33 person for the girls who'd read another book. The girls who didn't read a book during that time had actually gained weight, raising their BMIs by an average of .05.

The program director of Healthy Lifestyles, Dr. Sarah Armstrong, believes that books like Lake Rescue can be valuable tools for teaching children about healthy eating and lifestyle habits. In the book, Dr. Armstrong tells Time Magazine, the character "learns that she can become healthier, and the self-efficacy part, the 'I can do it' feeling resonates with the preteen girls."

So, if you've got a child on the verge of obesity, healthy eating and fitness are still the best ways to lose the pounds – but it looks like a trip to the library can't hurt, either.