sad to say, according to recent studies alcohol causes irreparable damage to DNA which can ultimately lead to cancer, so it's increasingly looking like a poor lifestyle choice on a par with smoking.
Drinking alcohol can cause cancer by damaging DNA, finds study | The Independent
The problem with addiction to alcohol (which may not be the case in the example that led to this thread starting) which was told to me by a recovering alcoholic, is that one drink is too many, and a thousand is never enough. It's binary. You simply cannot drink if you want to participate in any kind of normal life.
Most people are lucky. They can have a drink or two and just stop when they need to. Addiction means you are calling V1 as you raise your first glass and there's no stopping at that point, you have to continue. Best not to start. The so-called "functional alcoholic" does not and cannot exist in any kind of professional public transportation role.