When I start trying to convince myself I need another drink to maintain my buzz, I know intellectually that I’ve had enough. That thought is enough to make me remember the one time in my life I threw up and blacked out from booze, since the only clear thing I remember from that night is the feeling that I need to keep drinking or the buzz would fade.
Experience. I had to quit.
I’ve never vomited while drinking, so that’s out as an indication I’ve had too much. And I’ve had truly excessive amounts to drink many times, particularly for someone my size and gender. I’ve have no trouble keeping up with men twice my weight… Scottish genes. I’ve also only blacked out one time (we were drinking vodka in orange juice, and I was not paying any attention to how much liquor was in all that juice). My body seems to take whatever I throw at it… while I’m drinking. Afterward is not so pretty. I do vomit when I have a hangover migraine. So my real goal is to avoid hangovers. Which means not having enough to feel really drunk, not drinking for hours, and staying hydrated.
Luckily, I don’t get the urge to drink more/excessively when I’m already tipsy/drunk. It seems to have less effect on my judgment than for most people I know. I’ve never done anything out of my norm or stupid while drunk.
With me, it’s simple. I discovered way back in my early teens that even a sip of communion wine was enough to make me sick (note: not buzzed, sick). Armed with that information, I can safely say that my limit is a nice round number.
Same here, which is WHY I have to limit myself. The fact that I don’t feel the buzz as quickly doesn’t mean it’s not in my system, 'cause it is…the fact that I don’t feel it sometimes is kinda scary, and that’s exactly when I end up over-drinking. Sometimes it all catches up to me later, and I’ve had once where I felt very little to no effect…until I blacked out for the first and only time. Since then I don’t trust my head to tell me what’s enough; I just stick to a regimen, and if I don’t get ‘buzzed enough’, then I just stop, as otherwise I’m just gonna be sick.
TL;DR : A set limit is good, just BECAUSE you can’t judge what’s going to get you buzzed. Or too buzzed.
Basically this. When I’m “out of practice” and haven’t eaten a lot, one or two drinks will get a good buzz on. When I’m drinking fairly regularly, it can take four or five or more drinks before I feel the effects. I very rarely puke from drinking, so that’s not a good metric for me.
I can drink four beers end to end and still be OK but have to back off to about one an hour to maintain the buzz and not get too wasted. I don’t go out drinking much any more, but if I’m driving I might hold back a little. Of course the amount of food in my stomach and my overall “tiredness” play a big part too.
My personal problem is I black out before I get sick or start acting really nutso… I’ve just had to learn by experience where my point of no return is. It’s about 8 drinks at the moment.
For me experience as well, that’s why I’m glad that I had the ‘opportunity’ to start drinking and get shit-faced on many, many occasions before I ever was allowed near a vehicle. i now tend to refrain from drinking at all if i know I’m driving with the very rare situation where I’ll have one beer if I know I won’t be driving for at least an hour…never more than one though.
A different sort of explanation can be had through Calvin and Hobbes as the dad tries to explain trucks and bridges
I share the observation by Leo McGarry on West Wing:
I had to quit altogether. I was having too much fun.
My strict limit:
When it’s 3:17am and the bartender is screaming at me that if I don’t get the fuck out of here RIGHT NOW, he is calling the police. Then two of my friends grab me and drag me to the car.
That is when I usually try to stop drinking. Unless there is booze at home. 
My rule is, when I want to go on (and on, and on), it’s time to stop. It took me years of puking to learn this. :smack:
Eating until you can’t take another bite is as far beyond moderation as drinking until you fall down (or throw up, or black out).
The tip of my nose tingles and my cheeks get flushed. When that happens, I’m ready to stop. The last time I was falling down, passing out drunk was in '96 or so. I blacked out and never ever want to have that happen to me again. I so rarely drink now that it only takes about 3 beers to get the tingle, or one glass of wine. If I’m drinking amaretto and Pepsi, I can normally have about 5 of those. If I’m driving I stick to one beer.
I projectile-vomited on the Archbishop of the Diocese of Atlanta during my First Communion.
That was my limit - I haven’t had a drop since.
After much experimentation, for me it is leg tingling.