Letter writer Gilbert Ross implies that there is no comparison between eating pizza and smoking ("Eating a slice a pizza is not the same as smoking a cigarette," May 10). As a physician, I disagree.

Both tobacco and processed meats increase risk for cancer, heart disease and premature death. In fact, processed meat and other unhealthful foods kill more Americans annually than does tobacco.

But this isn't just my opinion. A large body of research supports the link between processed meat and poor health. The U.S. Department of Agriculture's dietary recommendations note the link between processed meat and colorectal cancer, and the American Institute for Cancer Research recommends avoiding processed meats.

With obesity rates projected to reach 42 percent by 2030, more Americans than ever are at risk for cardiovascular disease, diabetes and heart disease. Science and common sense connect this increase to poor nutrition, including a continual rise in consumption of meat and cheese.

President Obama is a role model for millions of Americans and has the power to influence what people eat. When he attends organized public events, he has a responsibility to set an example of healthful eating — for the sake of everyone's health.

Ulka Agarwal, Washington

The writer is chief medical officer for the Physicians Committee for Responsible Medicine.