Once I had some health problem. so i never took any thing which is effect in cold, such as bananas, cold drink etc. and one day one of my friend ask me to the Ganga bank to enjoy the Ganga in Bihar. and at time of coming back he offered cold drink. i denied due to my cough problem. The he order the waiter as "eak cold drink dena thanda aur eak garam". After departing i laughed very much on this thing.
I love eating and drinking cold things even during winter. I don't care if i have cold or flu i still take cold things and i know its not that healthy.
If drinking cold drinks was unhealthy, the species would have died out a few million years ago. Primitive man had 2 choices in winter - drink cold water (very cold) or die of thirst. Since we evolved to be able to drink water at near-freezing temperatures, there's nothing unhealthy about drinking something cold.