Narrator: This is Science Today. Contrary to popular belief, young women in their twenties can suffer from osteoporosis, a debilitating loss of bone mass often associated with older women. Dr. Aurelia Nattiv a professor of orthopedic surgery at UCLA, says several factors put young women at risk.

Nattiv: If a female has a history of loss of menstrual periods longer than three months and if they have a history of disordered eating patterns, or they exercise excessively or have a low percentage of body fat.

Narrator: Nattiv says it's important young women at risk have a bone density test - and since osteoporosis is a silent disease, the sooner the better.

Nattiv: A lot of people feel that if they have osteoporosis, that they would have bone pain or that they would have obvious symptoms and that's definitely not true. If a person is not aware of the risk factors, then the majority of those patients are going to be missed, because there aren't any symptoms until the end stage, until a fracture occurs.

Narrator: For Science Today, I'm Larissa Branin.