Nancy Shute

There's plenty of evidence that playing with a concussion increases the risk of long-term problems. But athletes, coaches and parents can be reluctant to call a halt. Then how can doctors do no harm?

Earlier safety studies of the vaccine for human papillomavirus found a higher risk of dangerous blood clots. But a study of 500,000 women and girls finds that the vaccine doesn't raise risk.

Lead exposure lowers children's IQ and causes aggression. But children exposed to low levels of lead show different symptoms, including more depression and anxiety, a study of preschoolers finds.

The live vaccine nose spray protects children better, a federal panel says, but pediatricians aren't sold. They say it's too risky for the many children with asthma or compromised immunity.

Drinking too much alcohol is a big factor in deaths of adults under age 65, CDC researchers say, from obvious risks like vehicle accidents to more subtle effects like higher rates of breast cancer.

Many people use products using benzoyl peroxide or salicylic acid to treat acne. The Food and Drug Administration says rare but dangerous allergic reactions have landed people in the hospital.

A newer form of mammogram that takes multiple X-rays makes it less likely that women will be called back for more screening, a study finds. But it's still too early to know if it increases survival.

Parents have been told they should read to their children early, but most don't think that means the day you bring Junior home from the hospital. Pediatricians say start now to help learning later.

Jason DaSilva was diagnosed with multiple sclerosis at age 25. He has applied his skills as a documentary filmmaker to show what it's like to quickly lose the ability to walk.

Children and teenagers who are aerobically fit and and have good motor skills do better academically, researchers say. But muscle strength doesn't help. And those motor skills may matter most.