Common ingredients in processed meat like salami, bologna, hot dogs and ham may increase the risk of bladder cancer. Nitrates and nitrites are frequently used to preserve lunch meats and hot dogs. They also add the familiar pink color and add to the flavor of such foods. But researchers have raised concerns about the safety of such compounds for decades. A joint National Institutes of Health-AARP study of more than 300,000 older Americans lasted seven years. The investigators found that those people who consumed the most dietary nitrite in processed red meat were 30 percent more likely to be diagnosed with bladder cancer than those who ate the least. Beef, chicken and turkey were not linked to a higher risk of bladder cancer.