Water and health: Follow your thirst
Most men can get the water they need from their usual diet and by drinking when they are thirsty.
Especially in hot weather, we are urged to drink adequate fluids and be on guard for dehydration. That may be why you see people toting bottled water everywhere, propelled by the myth that you need to drink eight glasses of water a day to be healthy.
Drinking eight 8-ounce (1 cup) glasses of water—about a half-gallon of fluid—is no small feat. But you may not need to drink that much water every day to prevent dehydration.