30 years after makers of aluminum cans changed their tabs to prevent them from being swallowed by children, a new study finds the problem remains.

Researchers at the Cincinnati Children's Medical Center say tabs on beverage cans today are still potentially unsafe.

Although the tabs are designed to stay attached to the can after opening, the study finds they're still easy to remove.

They cite 19 cases of children swallowing them from 1993 to 2009 at one hospital alone, most of the cases involved teenagers.

While most cases were resolved without surgery, the sharp edges of the tabs can injure the gastrointestinal tract, and many times do not show up on x-rays.
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New research shows high levels of physical activity may lead to arthritis.

Researchers at the University of California-San Francisco studied more than 200 middle-aged men and women who reported how much time they spent exercising.

Those who did the most exercise, especially high impact activities like running and jumping, had more damage to their knees… but felt no pain or other symptoms.

People who have these knee problems are more likely to develop Osteoarthritis, which affects about 27 million American adults. Researchers say low impact activities like swimming or cycling are easier on the knees, while still good for the heart.