The main cancer-causing culprits are nitrates and nitrites. These are added as preservatives and to give processed meats an appealing pinkish look. Nitrates occur naturally in such vegetables as lettuce and celery but in that form they do no harm. It’s when they interact with red meat that nitrates get troublesome. They form compounds such as nitrosomines, which are carcinogenic. The nitrosomines damage the cells in the lining of the bowel. Next step might be a visit to an oncologist. The dangers associated with nitrosomines have been known about for more than 60 years. Twenty-five years ago, a link was made between pregnant mothers eating hot dogs regularly and increased rates of brain cancer in children