It doesn't matter. Fist of all, it's a lot of genetic factor, some alkys die, some leave till 90. You don't know how your liver is going to take beating, so why take a chance?
Second, in most cases, it's not one, but combination of factors, like drinking, using pain medications, etc, etc...over the years it's all add up, and you don't want to contribute another factor to it...do you?
If you want to stay healthy, run blood test often, it's not expensive. Drink occasionaly, try to stick to injectables.
Even if you don't do all this, you will leave long, but most likely, a few last years of your life, you'll be very miserable.