How long can humans survive without water?

As a nutritionist, the figure for survival I've repeatedly heard is 48-72 hours without water and two weeks without food. However this varies on many different factors. It should be noted that from the point when you stop consuming liquid, to the point that you die, you'll not be able to function at full capacity. Death by dehydration is a nasty process involving incessant skin irritation, hallucinations, and the swelling/ cracking of the tongue.

As the many researches have found out that a human body is made anywhere from 50% to 70% water. Water plays a big role in your body. If there is no water the organs will not work properly and dehydration will start.

The approximate amount of days that you could go without water in your body is anywhere from eight to fourteen days. It all depends on the person. How fast the water and liquids are going out of the body. Sweat, urine, and tears go out of a humans body and it is very hard to predict how the water inside of you is being reduced and by how much.

This is very different from the food situation because in case of food, a human body is able to hold on as long as three months or even longer. It all depends on the person's shape and structure. If the person is heavy and weights a lot then it is most likely for them to survive for a while. But if the person is skinny and out of shape, that person will have less chance to surviving for as long the latter.

Drinking water is very important for proper functioning of the body. If you reduce the amount of water that you get every day, you are going to see some results like dizziness and headache. It is very important to have enough water every day. That is why when you are sick, you need as many liquids as possible because the water will clean out your body system and help you fight the disease.

In severe heat, an adult can lose as much as 1.5 liters of water through sweat alone. The main risk without water in high heat is that your body temperature will continue to rise and you'll suffer from heat stroke. Drinking water will cool you down and lower your core temperature.

With mild dehydration, you'll experience the following:
• Lack of saliva
• Decreased frequency of urine
• Decreased output of urine
• Deep color and strong odor in urine

Moderate dehydration:
• Even less urine
• Dry mouth
• Dry and sunken eyes
• Rapid heartbeat

Severe dehydration:
• No urine
• Lethargy and irritability
• Vomiting and diarrhea

Now back to the question at hand. How long can you go without water? Assuming you're in reasonable shape and in ideal conditions -- that is, not in the heat or cold and not exerting, a human can probably live for about 3 to 5 days without any water. Healthier humans can live another day or so longer.

This isn't something you should test. While people may fast or try a body cleanse without food, you should absolutely never go without water for more than a day.