From Wikipedia:
An American Institute for Cancer Research report found that consuming one 50-gram serving of processed meat — about one hot dog — every day increases risk of colorectal cancer by 20 percent.[21][22] The Cancer Project group filed a class-action lawsuit demanding warning labels on packages and at sporting events.[23] Hot dogs are high in fat and salt and have preservatives sodium nitrate and nitrite, believed to cause cancer.[24] According to the AICR, the average risk of colorectal cancer is 5.8 percent, but 7 percent when a hot dog is consumed daily over years.[24]
http://en.wikipedia.org/wiki/Hot_dog
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