Does eating and drinking cold stuff actually help ward off heat exhaustion, or it merely feels better?

Hydration: Fluid--Hot or cold or room temperature,but good volume of fluids, Rest,shade and get to a cool place

Ice water for heat: Heat build up during exercise can be dangerous. Sometimes the body cannot get rid of heat fast enough through perspiration. In those conditions,drinking a slurry of shaved ice (like snow cone ice) with water or Gatorade was effective in helping to remove some of the body heat in bicycling athletes. However,treating the entire body with an ice bath is the best way to lower the body temperature.

FeelsBetter: Drink plenty of fluids,get in to cool water,like shower or bath and use cool compresses on body.You need to drink fluids to prevent dehydration and can be at room temp but cold drinks will feel better than warm