Water is essential for all living things on Earth. That’s why scientists are always on the lookout for water on other planets and why we drink it every day. But have you ever wondered what would happen if you stopped drinking water? When we talk about “water,” we mean all drinks that contain water, like juice, soda, or tea. Just like breathing, feeling thirsty is a natural way our body tells us to drink water.
Water is the most common molecule in our bodies, making up about 65% of an adult’s body. It helps carry nutrients and hormones, keeps our body temperature steady, cushions our joints, and even keeps our eyes moist. Every day, we lose about 1.5 liters of water through urine and another liter through breathing, sweating, and other activities. That’s why it’s crucial to drink enough to replace what we lose.
The part of our brain that controls thirst is called the hypothalamus. It checks the levels of sodium and other substances in our blood. For instance, if we sweat a lot, our blood volume and pressure drop. The brain notices this and makes us feel thirsty.
If you can’t drink water when you’re thirsty, the first signs of dehydration appear. You’ll have a dry mouth, and your urine will become darker and smell stronger as your body tries to save water. Without enough water, your brain starts to suffer. You might feel dizzy, react slower, and even feel less pain. Studies show that when you’re dehydrated, your brain has to work harder to do simple tasks.
After a day or two without water, you might stop urinating, find it hard to swallow, have muscle cramps, and feel nauseous. Your body can go without food longer than without water. Eventually, you might become confused and your brain won’t work properly. Interestingly, many elderly people with confusion are just dehydrated.
If you go even longer without water, your skin might turn a grayish-blue color because your body is trying to keep its core temperature stable. After 3 to 5 days without water, your organs will start to shut down, including your brain.
Unlike the air we breathe, only 2.5% of Earth’s water is fresh, and most of it is trapped in glaciers, ice caps, and underground lakes called aquifers. Less than 1% is available for us to drink. Most of this water is used for farming and cooling power plants. In the USA alone, about 500 billion liters of freshwater are used daily for agriculture, and another 500 billion liters for power plants.
As our drinking water sources become more polluted, over 783 million people worldwide can’t access clean water. Scientists are working on solutions, like removing salt from ocean water, tapping into underground water sources, and creating new water filters.
In space, NASA has created technology that turns astronauts’ urine into water that’s even purer than what we drink on Earth. But we can’t just rely on technology. We need to understand and help solve the global water crisis.
If you want to help, consider joining World Water Day on March 22nd. There are many great projects, like water.org and the UNICEF app, which donates a day of clean water to a child in need for every 10 minutes you don’t use your phone. Small actions can make a big difference. All the money from this video will go to a water project called Morocco 5 Villages. Thanks for your support, and don’t forget to subscribe for more science videos!
Keep a water diary for a week. Record every drink you consume and note how much water it contains. At the end of the week, calculate your total water intake and compare it to the recommended daily amount. Reflect on how you felt each day and discuss any patterns you noticed.
Conduct a simple experiment to see how dehydration affects your cognitive abilities. Try solving puzzles or math problems before and after a period of not drinking water for a few hours. Record your results and discuss how dehydration impacted your performance.
Create a basic water filter using materials like sand, gravel, and charcoal. Test it by filtering dirty water and observe the changes. Discuss how this relates to the global water crisis and the importance of clean water access.
Research a country facing a severe water crisis. Create a presentation or poster that explains the challenges they face and the innovative solutions being implemented. Share your findings with the class to raise awareness.
Participate in a local or global water conservation campaign. This could be through a school project, a community event, or an online initiative like World Water Day. Document your involvement and reflect on how your actions contribute to solving the water crisis.
Here’s a sanitized version of the provided YouTube transcript:
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Every living organism we know of requires water to survive. This is part of the reason we search so diligently for water on other planets and consume it consistently every day here on Earth. So, what would happen to your body if you stopped drinking water? When we say “water,” we’re including all fluids that contain water, such as juices, soda, or tea. Much like the desire to breathe in oxygen, thirst is a survival instinct.
Water is the most abundant molecule in the human body, making up, on average, 65% of an adult. As a universal solvent, it carries nutrients and hormones throughout the body, regulates body temperature, cushions our joints, and even lubricates our eyes. You produce around 1.5 liters of urine every day, with another liter lost through breathing, sweating, and other bodily functions, so it’s essential that the body replaces this liquid.
The thirst center of the brain is located in the hypothalamus and constantly uses sensors in your blood vessels to monitor the amount of sodium and other substances in your body. For example, if you sweat too much, your blood volume and pressure fall. The brain detects this change and creates the urge to drink.
Now, what happens if you’re unable to satisfy this thirst? The initial signs of dehydration are obvious: a dry mouth, followed by darker urine with a stronger odor as your body attempts to conserve more fluids. The lack of water then begins to affect your brain. You might feel light-headed, have a slower response time, and experience a decreased ability to feel pain. In fact, when you’re dehydrated, your brain tissue literally shrinks. Studies have shown that dehydrated individuals require more brain power and oxygen to perform the same tasks as those who are fully hydrated.
After a day or two without fluids, you may stop urinating altogether, have trouble swallowing, suffer from muscle spasms, and likely experience nausea. Your body can survive without food much longer than without water, and at this point, digestion is not a priority. Eventually, individuals may become delirious with severely impaired brain function. Interestingly, studies of elderly patients with delirium found that many were simply suffering from chronic dehydration.
After even more time without water, blood flow to your skin decreases, which reduces heat loss but increases your core body temperature. This can lead to a grayish-blue tinge to your skin. Beyond 3 to 5 days without water, your body will begin to shut down its organs, eventually affecting the brain.
Unlike the plentiful oxygen we breathe, only 2.5% of all Earth’s water is fresh, most of which is locked up in glaciers, ice caps, and underground lakes known as aquifers, leaving less than 1% available for drinking. Most of this water is actually used for agriculture, with approximately 500 billion liters of freshwater used daily for farming in the USA alone, and another 500 billion liters used to cool electric power plants.
As our personal drinking sources become increasingly contaminated, over 783 million people on Earth are unable to access clean water. Scientists around the world are trying to find solutions to this problem, from attempts to remove salt from ocean water to tapping into underground aquifers and creating innovative water filtration systems.
In space, NASA has developed technology for astronauts to turn their urine into water that is more pure than what we drink on Earth. However, we can’t just rely on science and technology; perhaps the solution relies on us as a species to understand and contribute to this global water crisis.
If you want to help in the mission to end global thirst, consider participating in World Water Day on March 22nd. There are many amazing projects out there, such as water.org and the UNICEF app, which donates one day of clean water to a child in need for every 10 minutes you put your phone down. We’ll leave links in the description for these and other great water charities. Small investments can make a huge difference. We’ll be donating all the proceeds from this video to a water project close to us called Morocco 5 Villages. Thank you for supporting and watching, and subscribe for more weekly science videos.
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This version removes any informal language and maintains a professional tone while conveying the same information.
Water – A clear, colorless, odorless, and tasteless liquid that is essential for most plant and animal life and is the most widely used solvent. – Example sentence: Water is crucial for all living organisms because it helps transport nutrients and waste products in and out of cells.
Dehydration – A condition that occurs when the body loses more water than it takes in, leading to a lack of sufficient water to carry out normal functions. – Example sentence: Dehydration can cause headaches and dizziness, which is why it’s important to drink plenty of water, especially on hot days.
Nutrients – Substances that provide the necessary components for growth and the maintenance of life, often found in food and soil. – Example sentence: Plants absorb nutrients from the soil through their roots to help them grow and produce food.
Brain – The organ in the body that serves as the center of the nervous system, responsible for processing sensory information and controlling behavior. – Example sentence: The brain requires a constant supply of oxygen and nutrients to function properly, which is why a balanced diet is important.
Thirst – The sensation or feeling of needing or wanting to drink something, usually due to dehydration. – Example sentence: Thirst is the body’s way of signaling that it needs more water to maintain proper hydration levels.
Pollution – The introduction of harmful substances or products into the environment, which can damage ecosystems and human health. – Example sentence: Pollution from factories and vehicles can lead to poor air quality and harm both wildlife and humans.
Agriculture – The practice of cultivating soil, growing crops, and raising animals for food, fiber, and other products used to sustain and enhance human life. – Example sentence: Agriculture plays a vital role in providing the food we eat, but it can also impact the environment if not managed sustainably.
Glaciers – Large masses of ice that form in cold regions and move slowly over land, shaping the landscape and affecting sea levels. – Example sentence: Glaciers are important indicators of climate change, as their melting contributes to rising sea levels.
Solutions – Homogeneous mixtures composed of two or more substances, where one substance is dissolved in another. – Example sentence: In biology, solutions like saline are often used to create environments that mimic the conditions inside living organisms.
Temperature – A measure of the warmth or coldness of an environment or substance, which can affect the survival and functioning of living organisms. – Example sentence: Temperature changes can influence the behavior and distribution of animals in an ecosystem.
