Study Links Processed Red Meat to Bladder Cancer
Preservatives in Processed Red Meat, Especially Nitrite, May Play a Role in Cancer Risk
Aug. 2, 2010 -- Eating large amounts of processed red meats may raise the risk for developing bladder cancer, according to a new study.
Processed meats often contain the preservatives nitrate and nitrite. They are typically found in hot dogs, pepperoni, and deli cold cuts.
Researchers suspect that when processed meats are eaten regularly over time and in large quantities, these preservatives may interfere with the bladder’s lining when they are passed through the urine.
How the meat is prepared -- grilled, fried, microwaved, or broiled -- may also play a role in cancer risk.
Nitrite and Bladder Cancer
A team of researchers led by Amanda J. Cross, PhD, of the National Cancer Institute in Rockville, Md., followed 300,933 men and women aged 50 to 71 for more than seven years to evaluate the relationship between eating processed meat and the risk of developing bladder cancer. During the study, there were 854 cases (720 men and 134 women) of bladder cancer. The results are published in the online edition of the journal Cancer.
Participants filled out dietary questionnaires and provided information about their lifestyles, such as race/ethnicity, smoking, and education. Their total dietary nitrate and nitrite intakes were measured. The researchers also determined nitrite and nitrate content for 10 processed meats representing 90% of processed meats eaten in the U.S.
Researchers found a clear association between red meat cold cuts and bladder cancer risk. When they looked closer, they found a link between total dietary nitrite intake and bladder cancer risk but no clear link between total dietary nitrate intake and bladder cancer.
Bladder cancer was not associated with eating bacon, beef, hamburger, sausage, or steak, or white meat, such as chicken and turkey.
Those who ate the most red processed meats were more likely to be younger, less educated, less physically active, and eat fewer fruits, vegetables, and vitamins C and E. They were also more likely to be non-Hispanic whites, current smokers, and have a higher body mass index -- a measurement of height and weight.
"Our findings highlight the importance of studying meat-related compounds to better understand the association between meat and cancer risk," Cross says.