If the government is to try and ban private consumption of alcohol and tobacco, it must surely ban such activities as hang-gliding, skiing, rock-climbing and so on. Where should it stop? Rugby? American Football? Ice Hockey?
Insofar as the government has information not generally available about the merits or demerits of the items we ingest or the activities we engage in, let it give us the information. But let it leave us free to choose what chances we want to take with our own lives.