Eating a lot of meat may raise the risk of a certain type of stomach cancer, new research shows.
Researchers studied more than half a million adults in 10 European countries for nearly 6.5 years. Participants provided information about their diets at the study’s start.
The vast majority of people didn’t develop stomach cancer during the study. However, people who ate meaty diets -- and were infected with a certain bacterium -- were more likely to get a particular type of stomach cancer.
Red meats and processed meats stood out, write the researchers. They included Carlos Gonzalez, MD, PhD, of the Catalan Institute of Oncology in Barcelona, Spain.
The study appears in the Journal of the National Cancer Institute.
When the study started, most participants were 35-70 years old and weren’t known to have cancer. They provided blood samples and completed questionnaires about their diets and lifestyles.
Participants estimated their daily intake of these foods:
Red meat: pork, beef, veal, lamb Poultry: chicken, turkey, duck Processed meat: ham, bacon, sausages, processed meat cuts, hamburgers, meatballs, and pates Vegetables Fruit
The surveys also covered smoking, alcohol use, and physical activity. No one was asked to change their diets or lifestyles; the study was purely observational. That is, the researchers observed who got stomach cancer and who didn’t as the years passed.
During the study, 330 participants developed stomach cancer. That’s a “relatively low” number for such a big group, write the researchers.
Stressing the need for further study, the researchers note that people who ate more meat -- especially red meat and processed meats -- were more likely to get a particular type of stomach cancer called gastric noncardia cancer.
“Gastric” means stomach. “Noncardia” refers to the cancer’s location within the stomach. The cardia is the part of the stomach nearest to the esophagus.
That pattern was mainly seen in people infected with the intestinal bacteria Helicobacter pylori (H. pylori). H. pylori may cause gastritis, which is the inflammation, irritation, or erosion of the stomach’s lining. Without treatment, chronic gastritis can lead to ulcers and stomach cancer.
However, H. pylori is common and doesn’t always lead to ulcers or stomach cancer.
Other findings included:
Meat consumption varied widely between countries. People who ate the most red meat were more likely to have ever smoked than those who ate the least red meat. Smokers have increased risk for stomach cancer. People who ate the most processed meat ate fewer fruits and vegetables than those who ate the least amount of processed meat.
The study doesn’t prove that meat caused any cases of stomach cancer, and it doesn’t include dietary recommendations.
By Miranda Hitti, reviewed by Louise Chang, MD
SOURCES: Gonzalez, C. Journal of the National Cancer Institute, March 1, 2006; vol 98: pp 345-354. WebMD Medical Reference in collaboration with The Cleveland Clinic: “Digestive Diseases: Gastritis.” News release, Journal of the National Cancer Institute.