It’s one of the more hard-hitting attack ads on television, even by the standards of this bruising political season. But this commercial isn’t going after John McCain or Barack Obama.

Hot dogs are the target of “Protect Our Kids,” a new TV spot created by our organization, The Cancer Project, to publicize the link between eating processed meats and an increased risk of colorectal cancer. The commercial, which is airing around the country, features three young actors playing elementary school students who describe their lives from the perspective of adults with cancer. The ad invites viewers to help “get processed meats out of our schools.”

Provocative? Definitely. But as a dietitian who helped create the commercial, I think it’s critical for Americans to understand the solid science behind our concerns about hot dogs, pepperoni and other processed meats.

The ad is based on a comprehensive report released late last year by the American Institute for Cancer Research and the World Cancer Research Fund. After reviewing all existing data on nutrition and cancer risk, scientists concluded that processed meats increase one’s risk of colorectal cancer, on average, by 21 percent for every 50 grams of processed meat consumed daily. That’s about the size of a typical hot dog.

That news may shock frankfurter fans, but this landmark report can’t be easily dismissed. It is the product of a five-year process involving nine independent teams of scientists from around the world, hundreds of peer reviewers, and 21 international experts.

The report’s conclusion that processed meats increase colorectal cancer risk was based on a review of 58 scientific studies. The report clearly states that no amount of processed meat is considered safe to eat — it should be completely avoided.

That’s important for consumers to know. Every year, 160,000 Americans are diagnosed with colorectal cancer, and 50,000 die of it. About half of all cases are already incurable when found.

Some critics of our commercial claim there’s no harm in eating a hot dog occasionally. Unfortunately, however, Americans eat a lot of processed meats. According to the National Hot Dog and Sausage Council, more than 740 million hot dog packages were sold in 2007. Sixty-two percent of all Americans eat some form of processed pork, and the average person eats 32 pounds a year.

Processed meats are especially common in school lunch lines — indeed, some cash-strapped food service directors who would prefer not to serve these unhealthful foods are forced to do so because they are so cheap. That’s partly because the U.S. Department of Agriculture includes processed meat products as a reimbursable item for schools participating in the National School Lunch Program and National School Breakfast Program.

A survey our organization recently conducted found some school cafeterias serving processed meats at the majority of meals. Based on that data, it’s easy to envision kids at some schools eating bacon for breakfast, hot dogs for lunch, and then going home to have pepperoni pizza for dinner.

That habit could set the stage for cancer later in life. Indeed, America’s kids have never been at such high risk for diet-related diseases. More than 18 percent of children and adolescents are overweight. One in three will develop diabetes at some point in his or her life. Lifetime cancer risk is now one in three for women, and one in two for men.

Of course, processed meats aren’t the only high-fat, high-cholesterol foods in the school lunch line. And cancer risk is also increased by other factors, including obesity and diets low in fruits and vegetables.

The good news is that a growing number of schools are exploring creative, cost-effective ways to serve more fresh vegetables, fruits, and low-fat meatless entrees that reduce the risk of childhood obesity and encourage good eating habits.

But too many Americans don’t know about the power of wise food choices. That’s why public education efforts like our commercial are necessary — even if some consumers don’t relish the news that hot dogs can endanger their health.

Susan Levin is a dietitian with The Cancer Project, an affiliate of the vegan organization Physicians Committee for Responsible Medicine, 5100 Wisconsin Avenue NW, Suite 400, Washington, D.C. 20016; Web site: