SunburnThis is the standard problem with too much sun exposure. Sunburns can affect only the surface of the skin - or they can go deeper, and actually cause serious skin damage. Sunburns covering enough of the body can be life-threatening. Also, sunburns do not only happen on hot days. Sun exposure damages us through radiation, which is why we can be burned while snowskiing as easily as a hot day on the beach.
Read more: How to Treat a Sunburn
Not drinking enough water or sports drink can lead to dehydration. Exposure to the sun dries us out. When alcohol is consumed, dehydration is even worse. Untreated, dehydration can lead to shock and possibly become life-threatening. Vomiting and diarrhea make it worse, so travelers often can become dehydrated very easily.
Read more: Recognizing Dehydration Symptoms
Too much sun exposure on hot days can raise the body's temperature enough to cause heat exhaustion. This condition combines an increase in the body's core temperature with dehydration. Both are dangerous, and heat exhaustion - if left untreated - can lead to heat stroke.
Read more: How to Treat Heat Exhaustion
Heat stroke is what happens when heat exhaustion is not treated. There's no question that heat stroke is a life-threatening condition that needs emergency medical treatment.
Read more: How to Treat Heat Stroke
The opposite problem of dehydration is water intoxication (hyponatremia). This very rare condition comes most commonly from sweating all day and only drinking water. It's important to get electrolytes in the body as well as water. If you don't feel like eating on a hot day when you're sweating a lot, drink sports drinks instead of water.
Read more: Hyponatremia First Aid