Heavy beer drinkers have an increased risk of gastric cancer, especially if they possess a certain gene variant, a new study suggests.
People who drink two to three beers a day for many years have a 75 percent increased risk of gastric cancer, and those who have the gene variant called rs1230025 but aren't heavy drinkers have a 30 percent higher risk of gastric cancer, compared with people who drank less than a beer daily, the study showed.
But people who are both chronic heavy beer drinkers and possess rs1230025 have a more than 700 percent increased risk of gastric cancer compared with people who consume less than one drink a day and don't have the gene variation,said study researcher Eric Duell, a senior epidemiologist at the Catalan Institute of Oncology in Barcelona, Spain. The gene variant is common and is present in about 20 percent of the general population, he said.
However, wine and liquor don't seem to carry the same gastric cancer risks, Duell said.
"The share of the risk from total alcoholic beverages seems to be dominated by the alcohol contributed from beer consumption," Duell told MyHealthNewsDaily. "Consumption of wine and liquor did not show elevated risk of gastric cancer," which could be because heavy drinkers may be more likely to drink beer than other alcoholic beverages.
The findings are correlated, meaning there is a link between beer drinking and gastric cancer risk, but the results can't speak to whether one caused the other or some other factor is responsible.
The study was presented today (April 4) at the annual meeting of the American Association for Cancer Research.
Duell and his colleagues analyzed the alcohol consumption and gastric cancer status of 521,000 people ages 35 to 70, who were part of the European Prospective Investigation into Cancer and Nutrition in 1992 and 1998. Researchers noted whether the study participants consumed wine, beer or liquor regularly, and the location and severity of their gastric cancer, if any.
Researchers found that people who regularly consumed more than 60 grams of alcohol (equivalent to four to five beers) a day had a 65 percent higher risk of developing gastric cancer over the study period than people who regularly drank 0.1 to 4.9 grams of alcohol a day (less than a beer).
When researchers looked purely at beer consumption (instead of general alcohol consumption), gastric cancer risk increased, as it did when the researchers looked at people who were heavy drinkers and had the gene variant rs1230025.
Explaining the association
Gastric cancer, also known as stomach cancer, caused 10,570 deaths in the United States last year and usually strikes people ages 65 and older, according to the National Cancer Institute. One in 114 people will be diagnosed with the cancer in their lifetime.
Researchers aren't sure why only beer seems to produce this gastric cancer risk and not wine or liquor, Duell said, but it could be a combination of higher consumption of beer than wine or liquor, and the specific carcinogens that are produced when beer is metabolized.
When alcohol is metabolized in the body, a known carcinogen called acetaldehyde is produced. Beer in particular also contains low levels of a known animal carcinogen called N-nitrosodimethylamine (NDMA). Prolonged exposure to both acetaldehyde and NDMA, via daily beer drinking, could play a role in gastric cancer risk, Duell said.
And if heavy drinkers tend to drink more beer than wine or liquor, then those low amounts of acetaldehyde and NDMA could build up to increase gastric cancer risk, he said.
Because of these risks, people should avoid heavy consumption of alcohol, Duell said, though light to moderate consumption of alcohol is OK.
Next, Duell and his colleagues hope to do additional research to find more gene variants that could have an effect on gastric cancer risk.
Pass it on: Heavy beer consumption increases the risk of gastric cancer, and the risk is even higher if you possess a common gene variant.
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This story was provided by MyHealthNewsDaily, a sister site to LiveScience.