A few sips of beer and your face, neck and chest turn red. Your heart speeds up and you feel warm. People call it the alcohol flush or Asian glow, and it's a genetic signal worth paying attention to.
Two steps to clear a drink
Your body breaks alcohol down in two steps. First it turns ethanol into acetaldehyde, a toxic compound. Then an enzyme called ALDH2 turns acetaldehyde into acetate, which is harmless. A variant called ALDH2*2 cuts that enzyme's activity, so acetaldehyde builds up in your blood after even a small drink. The flush, the racing heart and the queasy feeling are what that build-up feels like.
How common it is
About 540 million people carry ALDH2*2, roughly 8% of the world's population, and it's found almost entirely in people of East Asian descent.
Source: McAllister, Sun and Gross, Journal of Biomedical Science, 2016.
Why the flush matters
Acetaldehyde damages DNA, and when it lingers, the tissues it touches first take the hit. A 2009 review led by researchers at the US National Institute on Alcohol Abuse and Alcoholism found that people with one inactive copy of ALDH2 are about 6 to 10 times more likely to develop oesophageal cancer than people with a fully working enzyme who drink similar amounts.
Source: Brooks et al., PLoS Medicine, 2009.
What to do if you flush
Treat the flush as information, not an inconvenience. Drink less, space drinks out, and skip the nights where the rounds keep coming, because the risk rises with every drink. Avoid pills sold to hide the redness: they mask the colour, but the acetaldehyde is still there doing the damage. Mention the flush to your doctor, too, as it's useful context for screening decisions.
Find out your type
Myoform's test reads your whole genome, ALDH2 included, so you know for certain rather than guessing from your reflection. Get your genetic test.
The Decode is for education only and isn't medical advice.