How much cancer can diet prevent?

Cancer is more complicated than heart disease, stroke, and diabetes.  It's pretty clear now that diet's biggest impact on cancer is avoiding overweight and obesity, and they are almost entirely avoidable.  Obviously, quantity of food is important.  And choosing the right foods can help us control our calories and weight.  It's the same market basket that's high in intact whole grains, fruits, and vegetables, and low in sugar, sugary beverages, refined grains, potatoes, and red meat.

Walter Willett is chair of the Dept. of Nutrition at the Harvard School of Public Health and professor of medicine at the Harvard Medical School.  He has published over 1,400 scientific articles on diet and disease. Excerpt from Nutrition Action Healthletter