"Heat stroke is a disease that leads to death—not just fluid loss"One of the most common and dangerous myths circulating among the public is that drinking plenty of water provides complete immunity from heat-related illness. "We need to distinguish between two completely different conditions: dehydration and heat stroke," the senior medic explains. I won't be dehydrated, but I can still suffer from heat stroke. Dr. Butner explains that the human body is designed to function within a temperature range around 37 degrees Celsius (98.6 Fahrenheit). Unfortunately, we see more deaths from heat stroke than from dehydration," he notes.