A Shot of Truth Behind the Bar

Have you ever wondered why some people can sip drinks all night while others feel the effects after just one glass?

Your genes — the tiny instructions you get from your parents — have a big say in this. How much you drink matters, but your genes can change how your body handles alcohol.

In this post we’ll look at one special gene and how it makes some people react differently. Next time you raise a glass, remember: your DNA might be calling the shots.

How Your Body Breaks Down Alcohol

Alcohol is the stuff in beer, wine, and cocktails. When you drink it, it goes into your blood very quickly — usually within an hour. Food in your tummy, fizzy drinks, whether you’re a boy or a girl, and how strong the drink is can all change how fast this happens.[1][2]

Most of the cleaning-up work happens in your liver. Your body first turns the alcohol into something called acetaldehyde. Then it turns that into a safer thing called acetate (the same stuff that’s in vinegar).[3][4]

Acetaldehyde is the “bad middle step.” If it stays around too long, it can hurt your cells and even raise the chance of some cancers. It is also the reason some people’s faces turn red when they drink![4]

Why Some Faces Turn Red: The Alcohol Flush

Your body uses a helper called ALDH2 to change the bad acetaldehyde into the safer acetate.

Some people have a slightly different version of the gene that makes this helper. That version works more slowly. When they drink, the bad acetaldehyde builds up. This makes the body release a chemical that opens up blood vessels, so the face (and sometimes the neck) turns red. People can also feel sick, get a racing heart, or feel like they have a hangover right away.[5]

This happens a lot in people whose families come from East Asia. That’s why people sometimes call it the “Asian flush.” If someone has one copy of the slow gene, the helper works only about half as well. If they have two copies, it barely works at all.[7]

Is This Bad?

Kind of.

Because the bad acetaldehyde stays around longer, people with this gene version who still drink a lot may have a higher chance of getting certain cancers in the throat or mouth.[8] The good news is that the red face and uncomfortable feelings often make people drink less — and that is helpful.

This risk can be even higher if they feel pressured to drink,[5] or if they have a faster version of another alcohol-breaking enzyme.[9][10][11]

Smart Tips If You Choose to Drink

1. Drink only a little
   No amount of alcohol is completely safe.[12][13] If you drink, keep it to about 2 small drinks a day for men and 1 for women (and none if you’re pregnant or breastfeeding). One small drink is roughly a can of beer, a small glass of wine, or one shot of strong alcohol.[14] Always check with a doctor if you have health problems or take medicine.
2. Never drink on an empty stomach
   Eat some food first. Drink slowly. Sip water between alcoholic drinks.
3. Try drinks without alcohol
   Mocktails, fruit juice, or water with fruit taste great and let you enjoy the party without the alcohol effects.

Your genes are part of you. Knowing how they work helps you make kinder choices for your body.