Researchers from the National Cancer Institute in the U.S used information from a study that began in 1995 and followed 300,933 older men and women from across the United States.
Participants filled out questionnaires on the meat they consumed, as well as how it was prepared and cooked. The researchers then matched this data to laboratory-measured meat components.
During the 7-year study, a total of 854 participants were diagnosed with bladder cancer.
The team found that the top fifth of participants in terms of processed red meat consumption had about a 30 percent greater risk of being diagnosed with bladder cancer than those whose consumption ranked in the bottom fifth.
Further, people whose diets included the most nitrites (from all sources, not just meat) and those whose diets had the largest amount of nitrate plus nitrite from processed meats, were also nearly a third more likely to develop bladder cancer compared to people categorized in the bottom fifth for consumption of these compounds.
No significant effects were found for total red, white or processed meat consumption. Similarly, no link was made between bladder cancer and the consumption of heterocyclic amines, polycyclic aromatic hydrocarbons, or total nitrites or nitrates from processed meat.
During the cooking process, nitrites combine with other chemicals that are naturally present in meat to form potentially cancer-causing compounds, which may then be excreted through the urinary tract where they can contact the lining of the bladder.
Other studies have linked the intake of processed meat to stomach, pancreatic and colorectal cancers
The Canadian Cancer Society recommends Canadians limit their intake of both red and processed meats.
All research on this web site is the property of Leslie Beck Nutrition Consulting Inc. and is protected by copyright. Keep in mind that research on these matters continues daily and is subject to change. The information presented is not intended as a substitute for medical treatment. It is intended to provide ongoing support of your healthy lifestyle practices.