御姐好，您还真说对了。美国黑人结肠癌还真比别的种族高。。。
http://www.cancer.net/cancer-types/colorectal-cancer/risk-factors-and-prevention
Race. Black people have the highest rates of sporadic, or non-hereditary, colorectal cancer in the United States, and colon cancer is a leading cause of cancer-related deaths among black people. Black women are more likely to die from colorectal cancer than women from any other racial group, and black men are even more likely to die from colorectal cancer than black women. The reasons for these differences are unclear. Noting that black people are more likely to be diagnosed with colon cancer at a younger age, the American College of Gastroenterology suggests that black people begin screening with colonoscopies at age 45 (see below). Earlier screening may find changes in the colon at a more treatable stage.
