Excessive mucus. Suggestions on this?

Hello Practo family, When I eat anything made of refined white flour(ex. Pizza, white bread sandwich, etc) or sugary( kaju Katli, regular tea), next day immediately infection spread through my respiratory system with yellowish cough and it takes 4-5 days to recover from that. When I have cold drink, I easily get sore throat. Also, when I eat food with even little bit of spice, it feels too spicy on the back of my throat. I research a bit and I get to know I have cobblestone throat meaning my body produces the excessive mucus and that makes easy to catch infection when I eat anything made of refined wheat flour or cold drink. How to get rid of this? Are there any suggestions on this? Let me know if more information is required! Thanks, Sagar