Water is essential for human survival. Going without water for just a few days can have serious health consequences. So how long can someone actually survive without any water? Here is a look at what happens to the body when you go without water for 7 days.
Quick Answer: No, you cannot survive 7 days without water.
The human body needs water to function properly. On average, a person can only survive 3-5 days without any water intake before dying of dehydration. Going 7 days without water would certainly result in death for most people.
What happens when you stop drinking water?
When the body lacks sufficient water, it becomes dehydrated. Mild dehydration occurs after just a few hours without water. As dehydration becomes more severe, bodily functions begin to shut down.
Here is what happens as dehydration progresses:
- After 1 day: Thirst, dry mouth, headache, dizziness, dark yellow urine
- After 2 days: Increased heart rate, rapid breathing, muscle cramps, dry skin
- After 3 days: Difficulty swallowing, minimally dilated pupils, white tongue
- After 4 days: Shriveled skin, fever, delirium, sunken eyes
- After 5+ days: Low blood volume shock, organ failure, death
Day 1 without water
On the first day without water, people will notice increased thirst and a dry mouth. Headaches, dizziness, and dark yellow urine are also common as the body becomes mildly dehydrated. Most people will feel irritated without adequate hydration.
The body can compensate somewhat for this mild dehydration by pulling water from cells and blood plasma. Losing water weight is common, along with dry eyes, fatigue, and constipation.
Day 2 without water
By day 2, dehydration is more severe. People will experience increased heart rate, rapid breathing, muscle cramps, and anxiety. The skin becomes dry and less elastic. Urine output decreases significantly.
At this stage, coordination and concentration are impaired. The mouth is very dry making swallowing difficult. Eyes stop producing tears. The body struggles to maintain proper blood pressure and circulation.
Day 3 without water
On day 3, people will have difficulty swallowing and speaking. The tongue may swell and become white or cracked. Pupils may minimize in size in response to dehydration. Dizziness and disorientation are likely at this stage.
Cells throughout the body are severely depleted of fluids. Muscle cramping continues. The skin is pale, shriveled, and lacks elasticity. The body struggles to maintain normal temperature. Survival past 3 days becomes unlikely.
Day 4 without water
By day 4 without water, the body’s cells are dangerously deprived of water. The skin becomes fully shriveled and eyes appear sunken. Fever may develop as the body loses its ability to regulate temperature.
Delirium and hallucinations are common. The heart rate is very high and blood pressure drops alarmingly low. Urinary output is minimal to none. Survival past day 4 is exceptional.
Day 5+ without water
Going 5 days or more without any water intake leads to full-blown circulatory collapse and organ failure. The body has pulled every last drop of water from tissues, blood, and organs in an attempt to stay alive.
Brain function deteriorates. Coma and seizures can occur. The lungs, heart, and kidneys begin shutting down. Death typically follows soon after.
Factors impacting survival time without water
How long someone can survive without water depends on various factors, including:
- Age: Infants and older adults have less water reserves and succumb more quickly.
- Body size: People with more body fat can survive slightly longer.
- Physical activity: Vigorous activity depletes water stores faster.
- Environment: Hot or dry conditions cause increased water loss.
- Illness: Fever, vomiting, diarrhea and burns hasten dehydration.
- Diet: Eating food provides some metabolic water.
- Psychology: Determination to survive may prolong life slightly.
How the body tries to conserve water
When faced with dehydration, the body activates physiological mechanisms to try to conserve water:
- The thirst mechanism kicks in to motivate drinking.
- Kidneys retain water by limiting urine output.
- Blood vessels constrict to maintain blood pressure.
- Sweating is reduced to limit fluid losses.
- Eating is inhibited since digestion requires fluids.
However, these mechanisms have limits. After 3-5 days without water, the body has lost too much fluid volume for these mechanisms to be effective. Organ failure and death result.
Treating dehydration
Mild dehydration can be reversed by drinking water. More severe dehydration requires emergency medical treatment with intravenous fluids or a nasogastric tube. Treatment focuses on restoring fluid volume and electrolyte balance.
Without prompt treatment, dehydration can lead to shock, organ damage, brain swelling, and death. Full recovery is possible if treated in time, although lasting complications can occur in severe cases.
Preventing dehydration
Since the body cannot survive long without water, preventing dehydration is vital. Strategies include:
- Drink plenty of fluids daily. Water is best.
- Drink before becoming thirsty as thirst indicates mild dehydration.
- Drink extra fluids with illness, heat exposure, or strenuous activity.
- Eat fruits and vegetables which have high water content.
- Avoid excess alcohol and caffeine which have diuretic effects.
- Monitor urine color. Dark yellow means more hydration is needed.
When to seek medical care
See a doctor immediately if you or someone you know:
- Has not urinated for 8 hours or more
- Has a fever over 101 F (38.3 C)
- Has symptoms like dizziness or rapid heart rate
- Cannot keep down any fluids due to vomiting
- Has a known medical condition putting them at risk
- Is showing signs of confusion or disorientation
Delaying treatment for dehydration can have serious consequences. Prompt medical care can help restore fluid balance and prevent complications.
Can you drink other liquids besides water?
Plain water is the best fluid for hydration. However, other liquids can also provide hydration, as long as they do not contain too much sugar, salt, caffeine or alcohol. Options include:
- Fruit/vegetable juices – limit to 4-6 oz to avoid too much sugar
- Milk – provides carbohydrates, protein, electrolytes
- Tea, coffee – limit caffeine versions as caffeine has diuretic effect
- Clear broths – provide sodium
- Sports drinks – provide carbohydrates and electrolytes
- Oral rehydration solutions – contain glucose and salts
The following liquids are not good choices for hydration:
- Sugary drinks like soda and fruit juice – too much sugar
- Alcoholic beverages – alcohol causes more fluid loss
- Caffeinated drinks – caffeine has diuretic effect
- Seawater or undrinkable water – contains too much salt
Can you get water by eating?
Eating fruits and vegetables that have a high water content can provide some hydration. Food provides approximately 20% of total water needs, with the rest coming from drinking fluids.
Foods highest in water content include:
| Food | Water Content |
|---|---|
| Cucumbers | 96% |
| Lettuce | 95% |
| Watermelon | 92% |
| Strawberries | 91% |
| Cantaloupe | 90% |
While eating fruits and vegetables can help with hydration, it is not a substitute for drinking fluids. Water and other beverages remain critical for avoiding dehydration.
Can you survive longer without water in cold environments?
There is a common misconception that you can survive longer without water in very cold environments compared to hot climates. However, cold temperatures do not actually prolong survival time.
In fact, cold environments may shorten survival for several reasons:
- Cold air is very dry, promoting fluid losses.
- Shivering and exercise stay warm burn calories needed to generate metabolic water.
- Blood circulates to core, depriving limbs of hydration.
- Hypothermia diverts blood from kidneys, decreasing urine output.
People lost in the snow may become dehydrated just as quickly as those in the desert. The best strategy is prevention – drinking plenty of fluids and avoiding becoming dehydrated in the first place.
Does lack of water cause brain damage?
Severe dehydration can cause brain damage and death. When the body loses too much fluid, blood volume drops. This reduces blood flow to the brain.
Potential effects include:
- Delirium and confusion
- Seizures
- Brain swelling
- Coma
- Brain cell death
The longer someone goes without water, the higher risk of permanent brain damage. Prompt treatment is vital. Providing IV fluids can reverse effects if caught soon enough. Delaying treatment can make damage irreversible.
Conclusion
Going without water for 7 days would be fatal for most people. On average, humans cannot survive more than 3-5 days without any fluid intake. The body requires water to perform basic functions and keep organs working properly.
Dehydration progresses rapidly without water, leading to organ failure, brain damage, and eventual death. While certain factors like age and environment impact survival time, no one can truly go a full week without drinking. Maintaining proper hydration is a daily necessity for good health.
