My daughter was diagnosed with polyps when she was 15. From the beginning......she is involved with chorus in school and was also getting coaching for the Christmas concert when a week before the concert she lost her voice. So we chalked it up to wintertime and working her voice harder than normal. With a little rest it seemed better, then in preparing for the spring concert the same thing happened. So I talked to our family doctor and he referred us to a specialist. After looking at her vocal cords, reviewing her life style, singing schedule, eating habits, etc. we were told she had acid reflux, compounded with the strenuous singing created polyps. She was put on medicine and restricted from singing, yelling(she is an avid volley ball player) and anything that would be considered strenuous on her vocal cords. We also changed her eating habits, not an easy thing for a teenager. Including what she ate and when she ate it. We cut out caffeine, spicy food, etc. and ate smaller meals (4 times a day instead of 3). Making sure not to eat anything at least 2 hours before bed. Also sleeping slightly elevated. Because we were told that polyps could come back, I also took her to a therapist to excercise her voice and to teach her how to use her singing voice properly in order to get back to the singing level she was at before all this started. All this seems to have worked for her the polyps are gone. I take her back yearly to have her vocal cords checked.
Good luck, talk to your doctor about all your concerns. Don't be afraid to ask questions.