New nitrite-cancer study creates confusion: A.M.I.F.
WASHINGTON – A study published on Aug. 2 in the journal Cancer that links nitrite and nitrate intake from processed meats to a potential increased risk of bladder cancer is the latest example of “nutrition whiplash” facing consumers, according to The American Meat Institute Foundation. James Hodges A.M.I.F. president, said the study creates needless confusion rather than providing clarity to the complex issue of diet and its effect on health.
Processed meat continues to be part of a healthy, balanced diet, and nutrition decisions should be based on the total body of evidence – not on one study that stands in contrast to the full body of research, Mr. Hodges emphasized.
A.M.I.F. charges the study erroneously perpetuates the myth that cured meats are the main source of ingested nitrite, whereas less than 5% of ingested nitrite comes from cured meats. Ninety-three percent comes from vegetables like lettuce, spinach, celery, cabbage and beets and from human saliva. Research conducted in the last 20 years had concluded the body makes nitrite as part of its healthy, normal nitrogen cycle.
Considered as the “gold standard” in determining whether substances cause cancer, the U.S. National Toxicology Program (N.T.P.) completed a multi-year study in which rats and mice were fed high levels of sodium nitrite. The study found nitrite was not associated with cancer.
N.T.P. maintains a list of chemicals found to be carcinogenic. Sodium nitrite is not on that list.
This is an epidemiological study, Mr. Hodges noted, which by itself is not sufficient to establish cause and effect. Rather, this type of study allows researchers to identify associations that may merit further study.
Even the authors of the study state the findings of their research are “tentative,” the relationship between dietary nitrite and nitrate was of “borderline statistical significance” and “not enough data was available to draw conclusive findings.”
“This study did not achieve the standard scientific threshold that would generate any concern at all, and it has already come under intense scrutiny from the scientific community because there is no data presented that is statistically significant by conventional statistical rules,” Mr. Hodges said.
“All of these studies struggle to disentangle other lifestyle and dietary habits from meat and processed meat and admit that they can't do it well enough to use their conclusions to accurately recommend people change their dietary habits,” he added. “What the total evidence has shown, and what common sense suggests, is that a balanced diet and a healthy body weight are the keys to good health. Meat contains protein, amino acids and essential nutrients like iron and zinc that can and should be part of a healthy, balanced diet and lifestyle.”