If you have chance to meet any doctor (physician) or nutritionist, what questions will you ask about the health of alimentary canal ( digestive system) ?

Explanation

I will ask the following questions about health of alimentary canal.
What is vomiting ?
What are the reasons for vomiting ?
What is the reason for constipation ?
Why do we feel nausea and headache ?
Why do some people suffer from ulcer ?
What kind of food should be taken by the people suffering from ulcer ?
Why shouldn't we eat junk food?
................... (You can add some more questions based on concept) .