Sugar and dumping syndrome

Hello to all! Question im new and starting my appts and approvals but always heard the same dumping what is exactly?! Is it like you get sick out if something you eat or its because you can eat anything sugary at all im going to meet woth my surgeon in april 30th and ill ask also but i want to hear from real people going through the process or that have experienced this before and last question why sugar will make you sick? Only ask cause i just cant sand fake sweetners so when the time is here dont know what to do help!