NEW YORK, (CBS NEWS).– Research tracking hundreds of thousands of adults suggests those who get 2 1/2 to five hours of moderate intensity exercise a week .. are less likely to develop seven kinds of cancer. The physical activity was linked to a lower risk of colon cancer in men and a lower risk of breast, endometrial, kidney and other cancers in women.

A new study suggests teenage boys who see peers abusing women and girls are two to five times more likely to engage in a variety of violent behaviors. Researchers from the University of Pittsburgh say adolescents who feel boys and girls deserve equal opportunities and respect had lower incidents of violent behaviors.

And transcendental meditation may help prevent abnormal enlargement of the heart. Doctors in Los Angeles tracked African Americans with high blood pressure for six months. They found patients who meditated kept their baseline heart size, while those who didn’t meditate had a 10 percent increase. An abnormally enlarged heart doubles the risk of heart attacks, stroke, and heart failure.

Those are some of the day’s top health stories.