How Long Can a Human Survive Without Food or Water?

How Many Days Can You Go Without Water and Food?

In a situation, where you do not have an access to water (and food), it is important to know, how long can you survive.

Most people would likely die within 3 -4 days without drinking or eating anything, and rarely one would survive over a week. But:

  • A 97 year old woman survived 8 days without drinking or eating anything under the rubble of her home after earthquake occurred in Iran in January 2004 (1).
  • Nearly all newborn babies, later became known as Miracle Babies, were found and rescued after being 7 days under the wreckage of a Hospital Juarez in Mexico City earthquake in 1985 (2).

Factors Influencing Length of Survival Without Water:

  • General state of health.
  • Percent of body water: newborn has 78% of body water, 1 year old 65%, adult man 60% and adult woman 55% of body water in average (3).
  • Percent of body fat: obese people have less water in their bodies.
  • Environmental temperature: in a hot, tropic climate, a person would likely survive less than 2 days without water.

How Many Days You Can Go Without Food (but With Water)?

A malnourished person without much body fat and muscles can die after not eating for few days. On the other hand, some people are able to fast (not eat deliberately and only drink water) for 40 days.

Factors influencing length of survival without food:

  • Starting body weight: physiologists agree nobody can survive losing 40% of his initial weight.
  • Initial amount of fat. When body does not get any food, it starts to use glycogen stores from the liver, which suffice for 1-2 days. After glycogen cessation, a breakdown of body fats starts to take place.
  • Initial amount of muscles. After cessation of body fat, body muscles start to be broken down.
  • “Basal metabolic rate” (BMR) – the speed of breakdown of nutrients at rest: a person with low BMR will burn his fat and muscles slowly.
  • A will to survive
  • Calories lost by physical and psychical effort
  • Environmental temperature: in a cold or hot environment, a body burns extra calories to maintain a normal body temperature.

Death After Discontinuation Artificial Sustenance

Death after discontinuation artificial feeding in terminally ill patients in hospitals typically occurs between 10 and 14 days (1).

WARNING:

  • Do not try, how long you can go without water – you can risk a serious and permanent kidney damage or even death. Also do not deliberately postpone drinking for any period of time unless your doctor has instructed you to do so.
  • When considering fasting (deliberately not eating for a certain period), it is highly recommended to visit your doctor, who can check your health and give you appropriate advice.

References:

  1. 77 years old woman survived 8 days without water (edition.cnn.com)
  2. Newborn babies survived 7 days under wreckage  (medbib.com)
  3. Percent of water in a newborn and adult  (madsci.org)
  4. Death after discontinuation artificial feeding  (scientificamerican.com)
About Jan Modric (249 Articles)
Health writer
  • emily anne

    I’m 14 and i am anorexic, i weigh somewhere between 72 and 26 lbs. Sometimes i go days without eating and i feel just sleepy. but when i do eat i feel like i am going to vomit, What should i do to be able to get to my normal weight without vomiting everytime i try to eat?

  • Jan Modric

    emily anne,

    can you speak confidently with anyone in live, an older friend, someone you trust? Orange or grapefruit juice goes quickly through the stomach. Drinking one cup (250 mL) of juice an hour, can provide some calories and fluid you need. Some plain cookies with juice could be also fine. But this is only a short term solution, since I can’t recommend you a complete diet, since I do not know you and your health condition. Foods that may cause nausea include meat, milk, salty foods, fast food…If possible, speak with your parents and you should visit a doctor since you may need some prescribed medication that can help to prevent vomiting.

  • jasminewok

    My mum was in a nursing home and I did not realise they were not giving her enough water to drink. Her skin was very dry because she was dehydrated. They rehydrated her at hospital but then they put her to sleep without food or water. She died after four days. She was 81.

  • Susie

    Dear Emily Ann. I hope you are still with us. Never take juice or cookies after not eating for several days. The juice has tremendous acidity and the combined sugar content between the juice and the cookies will plummet your blood sugar after a fast. If your tummy is empty and then you vomit with food, try ginger ale and nutritious crackers. Nibble on tiny pea size piece of cheese, a tiny piece of carrot dipped in peanut butter, two crackers, one thin, very thin apple slice, and sips of ginger ale. If it goes down ok, repeat every five-ten minutes for one hour. Wait two hours and do it again until your tummy is used to food. U can substitute toast squares, and pea size pieces of meat, fish or tofu. Good luck. Avoid cookies at all cost.