To thrive, many young female athletes need a lot more food

Participation in sports by girls and young women has soared in recent decades — by 560 percent among high school students since 1972, and 990 percent among college students, according to the Women's Sports Foundation. Highly committed young female athletes now run track and play soccer, basketball, water polo and other demanding sports that require strong bodies.

But many girls aren't eating enough to satisfy the physical demands of those sports, scientists say, and that's putting them at risk for health problems that can last a lifetime.