If you are planning a hike in the Grand Canyon there are some health hazard symptoms you have to be aware of. The biggest dangers are the heat exhaustion, the heat strokes and the Hyponatremia. The symptoms are nauseas, headaches, rapid pulse, vomiting and altered mental states. All these problems are due to the lack of water and salts in the organism. Drinking lots of water, eating energy drinks, and protecting your body from the sun will keep you safe. If you feel tired stop the hike.