This was a Quora answer that we shared originally with folks who were wondering about whether consuming alcohol would help protect them against the coronavirus. It didn’t seem broadly relevant, but since the US President recently speculated vaguely that injecting disinfectant would help fight the disease, we thought there might be some confusion out there, so we’d share this answer more broadly just in case it helps someone else!

The question: Does alcohol consumption have any effect on COVID-19?

The answer:

Consuming alcohol most likely makes it harder to fight off COVID-19 (see WHO guidance here).

Here’s the long answer as to why:

The concentration of alcohol that kills the virus on your hands is dangerous to drink. Alcohol is a critical component of hand sanitizer used to kill viruses and bacteria on your skin. However, to use alcohol-based hand sanitizer to kill the virus, the alcohol has to be at a high concentration by volume - 60% or higher (per the CDC). That concentration is required to be effective at dissolving the envelope protein around the coronavirus. But consuming even 1-2 mouthfuls of a 60% or higher ABV alcohol beverage can lead to alcohol poisoning per the CDC (for reference, even a shot of hard liquor is usually only about 40% ABV).
Even if you could safely drink the right concentration, it wouldn’t help you because you’re not applying it effectively by drinking it. When you use hand sanitizer, the idea is you’re killing the virus before it ever enters your body via your hand touching your face (when you touch your contaminated hand to your face, the virus gets into your body via the mucus membrane of your eyes, nose, or mouth). When you use hand sanitizer, you are applying the high-concentration alcohol directly to the virus, breaking up its envelope proteins. When you drink alcohol, though, it goes partially into your digestive tract and partially into your bloodstream, and in both cases, it’s heavily diluted. The concentration of alcohol in your blood after drinking it is nowhere near high enough to kill the virus. And even if you could somehow ensure it wouldn’t be diluted, you would not want the ABV in your blood to be 60%; you’d die at around 0.35%.
On top of that, regular heavy drinking compromises your immune system, making the chances higher that if you were infected, you’d suffer from a more severe form of COVID-19. This is the part where alcohol actually may hurt your chances of surviving COVID-19, per WHO guidance. Those with weakened immune systems are at higher risk for severe complications from COVID-19. And according to this 2015 research, 1) there is a clear association between excessive drinking and susceptibility to pneumonia (which is a severe symptom of COVID-19), 2) alcohol is proven to harm the functioning of the body’s immune system in multiple ways (via its effects on gut bacteria and immune cells in our airways). Put that together, and it’s clear that drinking is a bad idea for someone who wants to fight off this disease.

Hope this helps someone out there, and stay safe, everyone!