My ds use to always cough while eating or drinking anything cold (especially popsicles, ice cream, slushies, milk shakes, etc.) We were never given a specific reason for the cause; however, ds has asthma and reflux, too. Since cold air always triggered his asthma, I assumed it was either that or that combined with the reflux causing the problem. He has outgrown this issue. (He's 13 now.)