I've consumed more than 14 units in lunch hour, ffs! These units are utterly arbitrary and largely meaningless, of course.
In fact, they're widely considered to be counter-productive as, since nobody believes in them or takes them seriously, they actually discredit and undermine more sensible and realistic attempts by the medical profession to curb excessive drinking.
But of course doctors can't allow themselves to be seen as anything but finger-wagging puritans.