Acetaldehyde and alcohol
Alcoholic beverages are a significant source of acetaldehyde exposure. Acetaldehyde is the main metabolite of alcohol (ethanol). In many alcoholic beverages, it is also present as a by-product of the manufacturing process.
The microbes of the digestive tract can produce acetaldehyde from alcohol and then release it into saliva, gastric juice and the content of the large intestine. Poor oral hygiene increases local acetaldehyde formation from alcohol.
Acetaldehyde and genetic factors
Due to their genotype, people from East Asia suffer the most from the adverse effects of acetaldehyde. They have the aldehyde dehydrogenase-2 (ALDH2) mutation, which prevents the acetaldehyde formed in the body during alcohol consumption from being broken down into its end products – acetic acid and water. High concentrations of acetaldehyde accumulate in their digestive tract, and they also experience discomfort when drinking.
Europeans, on the other hand, have the alcohol dehydrogenases (ADH) enzyme mutation. As a consequence of this mutation, alcohol breaks down into acetaldehyde faster than normal, which, in this demographic group, causes high acetaldehyde concentrations in saliva during alcohol consumption.
Both enzyme mutations also predispose individuals to many of the adverse health effects associated with acetaldehyde exposure and considerably increase, for example, the risk of developing a variety of cancers. Almost all people native to Finland lack these key genetic factors.