The long-standing inverse relationship between education and mortality strengthened substantially later in the 20th century. This paper examines the reasons for this increase. We show that behavioral risk factors are not of primary importance. Smoking has declined more for the better educated, but not enough to explain the trend. Obesity has risen at similar rates across education groups, and control of blood pressure and cholesterol has increased fairly uniformly as well. Rather, our results show that the mortality returns to risk factors, and conditional on risk factors, the return to education, have grown over time.