Staying Hydrated: Why Our Bodies Need Water


Improving health and wellness can take many different forms. For example, you might start a new workout regimen, take up meditation, go vegan, or give up alcohol. But smaller changes can be equally important, and one habit that impacts the body in big ways is staying hydrated.

Why is it so critical? Severe dehydration can cause kidney and brain damage (and is even fatal), though it’s unlikely outside of extreme circumstances. However, even mild dehydration can lead to lethargy, headaches, moodiness, poor concentration, and inhibited physical performance, among other problems. Let’s take a look at the specific roles of water in the body.

Cardiovascular Health

Blood, which is over 90 percent water, is used to transport oxygen and nutrients to different parts of the body. But when you’re dehydrated, your blood volume is lower. Your heart then has to work harder to pump blood through the body, increasing your heart rate. Not only do oxygen and minerals not reach different parts of the body efficiently, but this puts strain on your heart as well. It’s also part of why dehydration makes physical activity more difficult.

Muscular Performance

Dehydration also impairs physical activity through its effect on muscle cells. When these (and other) cells aren’t sufficiently hydrated, they don’t work as well. As a result, you’ll experience muscle fatigue sooner and won’t be able to exercise as long or as hard as you can when hydrated.

Temperature Regulation

When the body heats up, due to either exercise or weather, blood vessels near the skin expand and water stored in the body is released as sweat. Without sufficient water, the blood vessels expand less and you sweat less, meaning your body won’t cool down.

Waste Removal

The kidneys and liver need sufficient water to filter waste from the blood and excrete it through urine. The digestive system also requires adequate fluids to process food, and staying hydrated helps prevent constipation. If you get dehydrated, your body won’t be able to cleanse itself or flush out bacteria.

Headache Prevention

For some people, dehydration can trigger or exacerbate headaches. When the body is dehydrated, the brain temporarily contracts and pulls away from the skull, causing a headache. Dehydration headaches can be dull and mild, but they can also take the form of intense migraines. If you’re prone to headaches, staying hydrated is especially important.

How to Stay Hydrated

Even if you’re aware of the many benefits of hydration, getting enough water can still be a challenge. Commit to drinking a full glass of water with each meal or snack, and drink a glass of water for each other beverage you drink. To drink more throughout the day, try keeping a cup or bottle of water at your workspace and carrying a water bottle whenever you go out. If you don’t like the taste of water, infusing it with fresh fruit or herbs will give it some flavor. The easier and more convenient it is for you to drink water, the more likely you’ll be to get enough of it.

What’s just as important as food and water? Sleep! Check out this article on the Importance of Sleep and How to Get it.

About the Author


Jennifer Ambrose

Jen is a freelance writer, blogger, and yoga teacher who left her office job in Boston to travel the world with her husband. She previously worked in international development and academic research, and served as a Peace Corps volunteer in Rwanda. Some of her biggest passions include promoting responsible and mindful travel and helping her students develop their personal yoga practice.