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How Long Can You Go Without Water

When we talk about intermittent fasting and restricting the amount of food we eat, going without water is not often the subject of discussion. However, it’s still a good thing to know— how long can you go without water? It’s an intriguing point and one that matters to the entire human race as a question of survival.

Here we will discuss all aspects of water, including its importance on a molecular level to every organism on this planet for digestion and temperature regulation, and the effects of going without it which can be catastrophic.

Overall, let’s dive into why water and hydration are important and other critical questions.

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What Is the Maximum Time an Average Person Can Survive Without Water?

Water— it’s what makes up most of our body’s percentage, and covers most of the planet that humans call home. Many scientists call water the medium of life or a universal solvent, as it’s something that is required to allow a person’s body to actually keep on living.

Unlike food, if you lose water in the body, it can be ultimately fatal. Even mild dehydration over a few hours can lead to extreme discomfort, whereas going days or even weeks without food will leave you hungry and irritable, but likely won’t lead to complete starvation.

The total time that an adult body can go without drinking water is about three days, according to experts.

Of course, while this can change depending on the climate, an individual’s body composition, and the amount of physical activity they are doing, the levels of body fluid necessary for sustaining life tend to run out very quickly.

According to researchers at George Washington University, the average temperature outdoors has much to do with how long you can last without water intake and relying on your own internal fluid stores.

For example, if you are stranded somewhere without access to food and water intake, but your body temperature is regulated and you are out of direct sunlight, able to better conserve more water within your body, you can prevent dehydration for a longer period.

But even in that instance, lasting longer than one week is an incredibly hopeful projection, especially given how much water the body needs.

And during exposure to extreme conditions, the total volume of water in your system will fall quickly if it’s extremely hot and your body temperature is high, where organ failure will happen sooner.

That’s because hydration is necessary for regulating your body temperature, and when out in a hot climate, more water is always better for anyone’s body.

The amount of water necessary to keep you alive does depend on individual factors as well as environmental ones.

Apart from being out in hot weather, your body weight, blood pressure, and overall blood volume from physical activity make your ideal fluid intake different— as well as how much lost water your body can handle.

Additionally, your overall health and well-being, sex, age, and any pre-existing health conditions will always affect how much water you can safely go without, and at what point losing water becomes a concern for organ failure and life.

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What Happens if We Don’t Drink Water for a Long Time?

The direct effects of a body without water are tied to the main reasons why hydration is important in the first place.

So, before discussing the symptoms of when we lose water in higher amounts than the body can restore, let’s talk about why water and staying hydrated is important in the first place.

The human body is made up of a complex living cell system, with each molecule working to keep the host alive. And while this is largely an unconscious act, like how we don’t think about breathing or blinking, certain daily practices are required to keep those cells thriving.

That includes drinking water and eating food to nourish and hydrate your body. And because the human body is composed of nearly 60% water, maintaining that water intake is essential for all bodily functions, including the organs, skin, muscles, and even bones.

Beyond the essential components of your body’s physiology and anatomy, your micro-functions also rely on fluids— and water, in particular, over other beverages. This includes keeping mucosal membranes moistened, forming saliva, keeping the eyeballs from drying out, and lubricating joints.

Now that we have a general overview of why drinking water is essential, we can go over some of the key things that occur in the body when dehydration sets in and you start to lose critical levels of water:

  • Dry coughing.
  • Dry mouth or sticky tongue.
  • Excessive urination as kidneys fail, or none at all.
  • Extreme disorientation.
  • Fatigue or dizziness.
  • Headache and delirium.
  • Heat cramps as the muscles seize.
  • Loss of balance.
  • Urine is a dark color and strongly scented.

How Does Food Affect Water Consumption

Water intake is not just necessary to keep your digestive system going and help your body flush waste, but it’s also supplemented by food in a symbiotic relationship.

Certain foods make up a surprisingly significant portion of daily hydration, and without food sources high in water, you would need to supplement more liquids into your diet.

Of course not all things you eat are amenable to improving hydration levels and retaining more water in the body, so let’s go over both the good and the bad when it comes to how food affects your water consumption.

Some foods that are high in water content and help keep your body hydrated include the following:

  • Apples.
  • Bell peppers.
  • Broth.
  • Cabbage.
  • Cantaloupe.
  • Cauliflower.
  • Celery.
  • Cucumber.
  • Grapefruit.
  • Lettuce.
  • Oranges.
  • Peaches.
  • Plain yogurt.
  • Skim milk.
  • Strawberries.
  • Soups.
  • Tomatoes.
  • Watercress.
  • Watermelon.
  • Zucchini.

However, it’s also important to remember the various foods that don’t help the body remain hydrated or even actively work to dehydrate you, including:

  • Alcohol.
  • Artichokes.
  • Asparagus.
  • Beets.
  • Coffee.
  • Energy drinks.
  • Fruit juice.
  • Soda.
  • Sodium-Rich foods (like potato chips and pretzels).
  • Soy sauce.

What Is Water Fasting?

Water fasting is a type of intermittent fasting that works by restricting all calories, solid foods, and other beverages besides water.

Intermittent fasting itself is a process of going without food for a determined period of time before using an eating window to refuel your body. It’s great for weight loss and a variety of other health benefits like decreasing insulin sensitivity, lowering blood sugar, and easing blood pressure, among many more advantages.

And when you embark on water fasting, the only thing you are allowed to consume during the fasting period is drinking water for the maximum calorie deficit and weight loss combination.

Even compounds within your water are not allowed, such as herbal or black tea. And, though lemon water doesn’t break a fast typically, adding lemon juice to your water is still discouraged during this method.

Some of the key benefits of sticking to a water fasting diet include lowering your at-risk status for many chronic diseases and health conditions by reducing the inflammation in your body. This helps prevent illnesses such as cancer, arthritis, and asthma, among others.

Additionally, water fasting is a great way to put the body into a state of autophagy, where the cells are able to rejuvenate and detox your entire system on a molecular level, shedding dead cells and any harmful substances.

Water Fasting Tips

If water fasting sounds like something you would like to try, then you’re in the right place! Read on for some great tips on how to get started and be successful with water fasting.

Schedule your fasting routine for a time when stress levels are low and your physical activity is limited. You will likely go through energy much faster and without food to refuel, you might feel tired and irritated.

Additionally, it’s wise to let your body rest during water fasting. According to one expert, this process is essentially “resetting your body”, which means that it’s alright to take the time for water fasting to work its magic and not push yourself!

Should Everyone Try Water Fasting?

Though fasting is typically safe for most people to try, there are some risk factors that make water fasting— in particular— unsuitable for certain groups of people.

Water fasting can make you dehydrated by removing the food source of fluids, as well as cause headaches, irritation, fatigue, and trouble sleeping, so don’t try it if you are:

  • At the risk of heart complications.
  • Below the age of 18.
  • Breastfeeding or pregnant.
  • Dealing with an eating disorder.
  • Diabetic.
  • Struggling with kidney disease.
  • Taking prescription medications.

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In all, water is indeed the source of life, and we wouldn’t be able to exist as a species without it. And because water is so critical, it’s important to not push the human body too far and not give yourself the proper amount of hydration.

That being said, water fasting is an overall safe and effective way to use hydration to your advantage and reset your entire body, while also being able to lose weight. Just make sure you fill up that water bottle and follow some of our helpful tips while fasting with water!


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This is an evidence-based article that includes scientific citations. DoFasting’s professional writers and editors prepared the content, which a team of medical experts verified to be accurate.

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