First, rinse with or drink clear water. Then chew some sugarless gum. Both of these practices will produce saliva, restore a healthy pH level in your mouth, and coat your teeth with nourishing minerals. Out of all the sugarless gums available, the best of the best are those that list xylitol as the first ingredient. Another option is to consume cheese, milk, or another non-acidic food or drink to conclude your meal.
After you have given your mouth time to return to a healthy pH, feel free to brush your teeth.
Well, when you're older, with iffy teeth, flossing removes trapped food that will cause inflammation and pain, the next day. That's personal experience.
Sadly I have to upvote this based on personal experience.
Was reading this thread right after the thread on John Goodenough. There are different things that happen as one gets older that one wishes didn't. Still, it beats the alternative.