When people drink alcohol, the alcohol is first metabolized into acetaldehyde by the enzyme alcohol dehydrogenase (ADH) in the liver, which then needs to be quickly converted into harmless acetic acid by another enzyme, acetaldehyde dehydrogenase (ALDH), and eventually metabolized out of the body. In many Asian populations, especially in East Asia, there is a common genetic variant that affects the activity of aldehyde dehydrogenase (ALDH2). Specifically, people who carry the ALDH2*2 allele have a greatly reduced activity of the ALDH2 enzyme, resulting in a slowdown in acetaldehyde metabolism and the accumulation of acetaldehyde in the body.
Symptoms caused by acetaldehyde accumulation include facial flushing, heart palpitations, nausea, headaches, and more, which are often referred to as Asian flushing reactions or alcoholic flushing. This reaction is a manifestation of alcohol intolerance and is a warning sign that an individual should limit alcohol intake. Therefore, if a person experiences these symptoms soon after drinking alcohol, it usually means that they are not drinking well.
The accumulation of acetaldehyde caused by long-term alcohol consumption can not only cause uncomfortable symptoms, but may also increase the risk of esophageal cancer and other cancers. This is because acetaldehyde itself is carcinogenic and can damage the DNA of cells, leading to mutations.
Therefore, for those who blush easily after drinking, it is recommended that they limit their alcohol intake and pay attention to their body's reactions. If you experience any serious discomfort, you should seek medical attention promptly. At the same time, understanding your genetic background and alcohol tolerance can help you make more informed health decisions.