Oddly, you can actually get sick from eating too much cold stuff, but it pretty much involves doing something like downing multiple ice cream shakes thus lowering your body temperature to the point where you throw up.

You can, also, drink too much water, but it's seriously like gallons. (Though you can also throw off your electrolytes if you just drink water and don't eat anything, particularly if you're sweating a lot. but this takes us back to - if the Gatorade actually tastes good, you probably need it.)