I t is possible to live for extended periods of time on little or no food. Research shows that a healthy individual can survive on 500 calories a day with no side effects and with plenty of water and a comfortable resting place can live approximately three weeks without food. During cold weather or periods of heightened activity more food is required to maintain a normal body temperature.
Water is much more important.
Two to three cups of water are required each day to stay healthy. It is wise to conserve the water in your body by reducing activities that may promote water loss. Finding water during the summer months is quite easy. It is wise to carry a water purification pump with you. This allows the hiker to make use of stagnant water in any situation and it is not necessary to carry water with you.