7 Answers

You could have a sinus problem, on the other hand try giving it a good blow before you start to eat, and no it,s not a euphemism.

Are you eating spicy foods?  Breathe through your nose when eating not your mouth (in other words, chew with your mouth closed), this may help to keep your nose dry.  My grandfather always chewed with his mouth open and his nose ran the whole time. 

Could be some sort of food allergies...Pay attention to what you are eating when this happens......keep notes.........

I believe it's a thing that comes with age. I have the same problem and I don't eat spicy food or eat with my mouth open.

Always need a napkin not for my mouth but for my nose.

Try nose plugs .Ear plugs work to keep out sound Like the "wife "shouting at me ,could be spicy food ..

Makes for an interesting salad dressing.

That is just TMI.