Colonoscopies in younger women can significantly cut their risk of colon cancer, according to a new study published in the journal JAMA Oncology. Researchers at Massachusetts General Hospital analyzed data from over 100,000 U.S. women. They found that women who started colonoscopy screening at age 45 had a 50 to 60 percent lower risk of developing colon cancer than those who had no screening. Colon cancer is the third leading cause of cancer death in both men and women in the U.S. Colon cancer cases among people younger than age 50 rose over 50 percent between 1974 and 2013. While this study shows the benefits of earlier colonoscopy screening for younger women, the findings also likely apply for men.