Why some Jews should take it easy on the le'chaims?

Know anyone whose face turns red after drinking alcohol? According to one source, "Although most prominent in Chinese, Japanese, and Koreans, some people of Jewish descent reveal high levels of acetaldehyde and might experience the alcohol flush reaction as well." Now it appears that this condition is associated with a cancer risk.

People whose faces turn red when they drink alcohol may be facing more than embarrassment. The flushing may indicate an increased risk for a deadly throat cancer, researchers report.

The flushing response, which may be accompanied by nausea and a rapid heartbeat, is caused mainly by an inherited deficiency in an enzyme called ALDH2, a trait shared by more than a third of people of East Asian ancestry — Japanese, Chinese or Koreans. As little as half a bottle of beer can trigger the reaction.

The deficiency results in problems in metabolizing alcohol, leading to an accumulation in the body of a toxin called acetaldehyde. People with two copies of the gene responsible have such unpleasant reactions that they are unable to consume large amounts of alcohol. This aversion actually protects them against the increased risk for cancer. [...]

The malignancy, called squamous cell esophageal cancer, is also caused by smoking and can be treated with surgery, but survival rates are very low. Even moderate drinking increases the risk, but it rises sharply with heavier consumption. An ALDH2-deficient person who has two beers a day has six to 10 times the risk of developing esophageal cancer as a person not deficient in the enzyme.

Reducing drinking can significantly reduce the incidence of this cancer among Asian adults. The researchers calculate that if moderate- or heavy-drinking ALDH2-deficient Japanese men reduced their consumption to under 16 drinks a week, 53 percent of esophageal squamous cell cancers in that group could be prevented. [...]

Sounds like you're safe if you only drink to make kiddush, drink four cups at the seder, etc., but it's something to think about.