A study by Harvard researchers warns carnivores of the obvious and not-so-obvious pitfalls of their diet. Frequent bacon consumption may increase the risk of bladder cancer—and so could the skinless chicken served in dining halls.

Men and women who eat bacon five times a week or more have a 59-percent-higher likelihood of developing bladder cancer than those who never eat bacon.

Consuming, with similar regularity, chicken cooked with the skin taken off makes one 52 percent more likely to develop the disease, according to the study, published in this month’s issue of the American Journal of Clinical Nutrition.

There are at least 10 chicken dishes on the menu between today and Monday, according to the Web site of Harvard University Dining Services (HUDS), and many of them—from chicken pot pie to chicken marsala—are skinless.

The research team, led by Harvard School of Public Health Assistant Professor of Epidemiology Dominique S. Michaud, analyzed two well-known cohort studies, the Nurses’ Health Study and the Health Professionals Follow-Up Study.

The research was unique for its huge sample size—47,422 men and 88,471 women—and for examining the consumption of specific types of meat in relation to bladder cancer, Michaud wrote in an e-mail.

The study used questionnaires to survey participants’ food consumption over a period of up to 22 years.

Meats such as hamburgers, hot dogs, processed meats, and chicken cooked with skin were found to have no significant association with bladder cancer risk.

Bacon, though, contains high concentrations of nitrosamines, known carcinogens.

And heterocyclic amines, carcinogenic compounds produced when foods are cooked at high temperatures, are more common in skinless chicken than chicken cooked with its skin on.

Nevertheless, the results involving skinless chicken were unexpected, Michaud said.

She cautioned that the findings are still new and that people who eat skinless chicken frequently should not necessarily panic.

“This is really the first study to see this association,” she wrote.

Students interviewed yesterday in dining halls said they found the study’s results surprising but not alarming.

“That’s impressive...I did not know that,” said Alejandra Guzman ’07, who estimated that she eats chicken seven times a week.

Asked whether study findings affect her dietary habits, the biology concentrator said, “if I think it’s important, I try to look into the study, but at the same time, anything you eat can make you sick.”

“One study is one study,” said Dara F. Goodman ’07, who estimated she eats chicken “five to ten times” a week.

Bacon is served about once per week in HUDS dining halls, while chicken is available on a daily basis, according to Crista Martin, HUDS assistant director for marketing.

“Fifty percent of our entrees are probably chicken,” said Martin.

Michaud also added that bladder cancer is four times more common in men than in women.

According to the American Cancer Society, about 61,000 people will develop bladder cancer this year.