It's okay, I've been living like this my whole life. And I don't have any particular problems with my teeth or digestion.

Everyone says that, huh?
The bacteria that affect the mucous membrane are in the oral cavity. We open our mouths – there's contact with the external environment.
It is necessary to refresh the oral cavity for the normal functioning of the salivary glands (they secrete a secretion - saliva, which participates in the process of digestion (enzymatic function).
When you brush your teeth, you actually feel less hungry. But this is only if you brush and then immediately sit down to eat. Time is needed. And you shouldn't brush your teeth immediately after eating.