You're right that simply drinking (non-alcoholic) or eating behind the wheel isn’t a specific offence on its own under UK law. But as you probably know, it can still lead to charges like careless or dangerous driving if it affects control or attention—even momentarily. It really depends on how it's interpreted in context, which is why so many end up with convictions when incidents occur. I think that's what the earlier point was getting at.
Did you not read my previous threads?
There is nothing to stop you drinking alcohol whilst in the vehicle as the same rules I outlined still apply. (Look at my first post on this subject), hence the reason I asked for a specific act and section that outlaws drinking alcohol in the vehicle.
There isn't one it all comes under (as you have repeated what I have already said,) either careless driving in the case of a catastrophic crash, dangerous or death by dangerous driving,, or failing to maintain proper control of the vehicle! 🙄
But if you know something I don't after 45 years in traffic law enforcement, investigation and teaching, then please tell me, I am always happy to learn!