How long does it take to die from dehydration? ( Days or Weeks? )

If you ever had a hangover, then that is exactly how it feels to be severely dehydrated. Dying from dehydration is a fairly slow and painful death, so make sure you have plenty of water, especially if you are hiking in remote areas.

It takes around 3 days to die from dehydration, although depending on your physical condition, your age, and the local climate will directly affect how long will it take to die from dehydration, there are people who died from dehydration in less than a day, on the other hand, there are people who survived without water for a week.

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There are many life-threatening situations during any kind of SHTF event, but the one which most people will face is dying from dehydration. For those who do not know what the term dehydration means, it is the term used by people to describe someone or something which needs water to survive and doesn’t have the ability to find water, which eventually will lead to death due to lack of water aka dehydration.

Most people are not prepared for any kind of SHTF situation, and in case of a drought or any other kind of SHTF situation where the lack of water is an imminent threat, this unpreparedness could end up deadly. According to FEMA, every household should have at least 3 days worth of water for each of its family members. However, this is in the best-case scenario, as most people are either too lazy or lack the necessary space to stockpile water.

If you read my article How long can you store bottled water? ( In your Home, Garage or Car ), you will find that stockpiling water long term in water bottles is not always your best option. Dehydration affects everybody, some people with health issues or the elderly and the young will feel its effects sooner than your average person. One of the most crucial differences in how long will it take people to die from dehydration is their weight.

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Causes of dehydration

There are a lot of causes of dehydration, but the most obvious one is the lack of water. If you have read my article ( Top 10 ) Things to take on a desert island, you already know that in a desert island where there is no freshwater the number one killer will be death from dehydration. You do not even have to be in a desert to die from dehydration, there are a lot of events that could lead up to it, and in some cases, it could even be fatal.

In my recently written article Best survival movies ( Top 18 ), you will find a lot of movies are based on accidents where the person has either injured themselves so they can not travel to find water or they have some kind of accident on sea or in the desert.

Food can cause dehydration

When our body is digesting food it needs water to do it, if the food is salty or spicy it will need a lot of water. This is why after a big dinner some of us wake up during the night to drink water, if you do not drink water you will find going back to sleep extremely hard. This is the body’s natural reaction when it needs something you get a craving, we all know how bad hunger and thirst can get especially if we are doing some kind of physically intense activity.

Foods like pasta, rice, fried potatoes and most of the cooked meats will need a lot more water to digest than something like a broth or soup which has a high content of water in it. This is why some people who are extremely dehydrated and even starving, once they eat some food it could end up shutting down their entire body due to lack of water, which will inevitably lead to death by dehydration.

Salt and spices can cause dehydration

Most people do know that salt and spices do retain water in the body, the more salt and spices we consume the thirstier we get. Usually, the salt and spices are combined with different kinds of foods, generally with meat products which will dehydrate you even faster. The body needs salt to function correctly, without it you could develop some serious health issues, but too much salt consumed in a short period of time will lead up to dehydration. If you are wondering how can you clean yourself without water then check out my recent article How to clean clothes without water ( Top 13 Ways ).

Environment and climate can cause dehydration

Most people who die from dehydration are due to their local environment, people stranded in the desert need a lot more water to function than people in a more tropical climate. People living in the desert have adapted to the desert environment and they could survive longer without water than your average person, mostly as these people do know how and where to find water even in the middle of the desert.

You might think that people in a colder environment are fairly safe against dying of dehydration as there is plenty of snow around. This is true to some extent, although eating snow with a weakened body could prove deadly. This is why most survivalists melt the snow before consuming it, otherwise, the snow due to its lower temperature could damage your organs and in some cases, it will even dehydrate you even further. If you read my article Does eating snow dehydrate you? ( How and Why? ), you will find that eating snow will actually dehydrate you.

Physical activity causes dehydration

Physical activity produces a lot of heat and needs a lot of energy, the body will try and cool itself down with sweating but if you are dehydrated the first sign of trouble is that you can not sweat anymore. Most prolonged physical activities will need a lot more water, this is why bodybuilders, mountain climbers do pack extra water as they do know that with the extra effort their body will need a lot more water. Eating a big spicy meal before any physical activity will dehydrate you even faster, and if you can not find freshwater quickly you might get seriously dehydrated in a matter of only a couple of hours.

Drinking alcohol does dehydrate you

If you have ever been hungover then you probably know how dehydration feels. In fact, some survivors compared the sensation of dying to thirst to an extreme hungover. Alcohol is considered toxic by the body and it will do everything in order to flush it out of your body. While some parts of the alcohol will be broken down and digested by your stomach and liver, most of it will be flushed down the toilet.

While drinking alcohol the body increases its demand for water as alcohol, in fact, dehydrates you, but while the person is intoxicated will confuse this craving for water for the craving for more alcohol and this is why some people drink themselves under the table. Even after the person has stopped drinking alcohol and he is already sleeping the body will work overtime in order to eliminate as much of the alcohol as possible, this requires a lot of water and energy, this is why you wake up thirsty after a night of drinking.

Dehydration timeline

Knowing the dehydration death timeline signs will help you identify how seriously you are dehydrated. If you are planning a longer journey where you are not sure that you will find any freshwater then you need to keep an eye out for the dehydration signs. Starting from the first timeline to the last one the person’s condition will spiral out of control, generally speaking, the body will hit its tipping point after the heart starts to beat much faster than usual.

There are people who have survived severe dehydration at different points of the dehydration timeline, but generally speaking the further in the timeline the person is the harder it will become for them to survive even if he has been rescued and properly hydrated. At the lowest point of the timeline, the body is far too weak to use any additional water if he is rescued, in this case, most survivors will get an IV which will hydrate the body directly in the veins rather than relying on the organs to absorb and to distribute the water.

In some extreme dehydration cases, it has been shown that the brain will only partially function, mainly the primitive brain will function properly which aids in breathing and dictates the fight or flight response. Some people have managed to be rescued while being almost unconscious and just kept on walking until they eventually have been spotted by somebody. Dehydration is very serious as even if it doesn’t kill you it could lead up to irreversible organ damage and failure.

Thirst and dry mouth caused by dehydration

One of the tell-tale signs that you are dehydrated is thirst, depending on the severity of dehydration this could also come with a dry mouth and no saliva. If you are at a point when you are not only thirsty but your mouth is also dry then you need to find water asap. From this point, onwards depending on the ambient temperature things could go from bad to worse in a matter of hours. Once you cross the tipping point you will no longer have any energy to search for water and in some cases even to absorb it if you find some.

Constantly tired caused by dehydration

Most people are used to drinking a lot of soda drinks during the day, some families do not even drink water whatsoever. In this case, you and your family members are probably dehydrated to a certain point. If you constantly wake up feeling tired and sleepy no matter how long you have slept, it could be that you are just dehydrated. Fatigue and dehydration go hand in hand, once you get dehydrated you will start feeling more tired, the longer you are dehydrated the worse this symptom becomes, this is why people dying of thirst tend to go to sleep before they die.

Yellow urine caused by dehydration

Have you ever noticed that the color of your urine tends to change during the day? Usually in the morning is dark yellow and in the afternoon it is almost transparent, this is mostly due to dehydration. Dark yellow urine means that your body is dehydrated, while almost colorless urine means that you are well hydrated, although you probably know this due to the frequent bathroom breaks.

Constant headaches caused by dehydration

As with any other organ, the brain also needs water to function. If you neglect your water intake it will lead up to dehydration which will cause you a headache. The severity of the headache will be different from person to person and how dehydrated they are, but this is one of the easiest signs to notice that you are dehydrated. Some people do not know that they are dehydrated and have constant headaches which they try to alleviate with medicine, but no amount of medicine seems to help.

Most likely these people are used to drinking only soda every day which will actually dehydrate you, if you are suffering from constant headaches start drinking more water and you will see that your headaches will start to be less and less frequent.

Dry skin caused by dehydration

Some of the water that comes out of your body is through your skin, the more hydrated you are the smoother your skin is. After you take a shower you will notice how smooth your skin is in comparison to before, this is mostly due to the skin absorbing some of the water to hydrate itself. If the body doesn’t have enough water to hydrate the skin cells then you are severely dehydrated, and you will notice that your skin is rough, and in some cases, you develop small white skin flakes on your elbows.

Low blood pressure and dizziness caused by dehydration

Having low blood pressure leads to dizziness, this is mostly due to the fact that the body doesn’t have enough water with which to pump necessary blood, oxygen, and nutrients to the brain. If you are dehydrated and stand up quickly you might notice some lightheadedness as well. Low blood pressure in combination with dizziness and dehydration is a recipe for a disaster, studies have found that people who are dehydrated tend to lose some of their cognitive functions as well.

Rapid heart rate caused by dehydration

If you are dehydrated and experiencing rapid heart rate it means that you are close to dying. As the body doesn’t have enough water to function correctly, the heart will start pumping faster to supply the vital organs with what little water the body has left. The more dehydrated you are the thicker the blood is, which means that the heart will pump even faster to a point where it is no longer possible for it to pump any blood, once you reach this part you are dead.

Confusion caused by dehydration

If you have watched any kind of survivalist movie then you probably noticed that right before the person dies it becomes confused and in some cases experiences hallucinations as well. Without an adequate supply of water, oxygen, and nutrients the brain will not function properly. As the severity of the dehydration progresses so does the level of confusion increases, in some cases, this could also lead up to irreversible brain damage and even death.

Shock and coma caused by dehydration

Once the body is severely dehydrated and the blood can not supply the cells and the brain with enough oxygen the body will go into shock. Generally, the shock produced by dehydration lasts only for a few minutes after which the person falls into a coma and the body starts shutting down non-vital organs. Once the body has crossed the point of no return the person will die if he is not rescued, even if he is rescued he could suffer from organ failure and possibly brain damage.

How long does it take an overweight person to die from dehydration?

You might think that obese people would survive the longest without water due to their larger body size which contains much more water than your average weight person. This is true to some extent, although obese people will feel the effects of dehydration much faster than average people. Obese people do have more water in their bodies, but the more obese a person is the fewer muscles they have, this, in turn, makes every movement costing a lot of energy and sweat. If you have ever seen an obese person sweating and gasping for air just from a simple walk you know what I mean.

Obese people in addition to suffering from dehydration will also develop complications much faster than average built people. Most people think that obese people have larger organs which means they can absorb and withhold a larger amount of water, however, this is false, an obese person has more or less the same size organs as an average built person. The only big difference is that these organs are wrapped around in fat, slowly suffocating the organs.

Bigger bodies need more water to function, once the body is starting to dehydrate it will start breaking down the fat cells which do contain water. However, this is a high energy consumption process and it will only weaken and dehydrate the individual even more. Generally speaking, an obese person could die from dehydration in around 2-4 days, depending on the environmental conditions this could decrease dramatically.

How long does it take an average built person to die from dehydration?

Average weight people who have a fairly active life and even might work out on occasion are better equipped to staying hydrated. Generally speaking, their bodies are much more efficient in storing, absorbing, and eliminating water. As these people have lower body fat to muscle ratios, they do not need as much water or even food to maintain the same weight as obese people. Generally speaking, your average person could die from dehydration after around 3-10 days, this time could go up and down depending on the local climate. Average built people due to their smaller bodies when compared to obese people, need a lot less water for their organs to function correctly.

How long does it take a skinny person to die from dehydration?

Most skinny people tend to have more or less the same weight their entire life. These people’s nutrient and water absorption are relatively fast which means that their body doesn’t absorb all the nutrients and water it can from their food and water. This is why you see a lot of skinny people who can eat everything, they are in a constant battle with hunger and dehydration due to their inefficient bodies.

Due to their lower muscle mass and almost no fat, these people can also survive without water for around 3-8 days. Their bodies need a lot less water to function correctly, but their bodies have a hard time retaining any water. Some skinny people will rarely sweat, this is mostly because they are almost constantly slightly dehydrated, without even them knowing it. Sweating is a bodily function which in order to cool down the body’s temperature will sweat water, the body is unable to sweat when the humidity is too high or the body is dehydrated.

In conclusion

Dying from dehydration will take around 3 days for your average healthy person, for the elderly and people with preexisting health conditions this number could drop down to even a few hours. One of the biggest factors which will dictate how long can a person go without water is the local climate, people suffering from dehydration in the desert could die in a couple of hours, while people in a more temperate climate could end up living for a couple of days.