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You’ve heard it time and time again: H2O is essential. But what exactly does staying hydrated do? Here are 13 reasons water is vital for your health — and why you gotta drink up.

1. Water makes blood

Your body turns water into blood and other vital fluids. These fluids serve as a transport system for oxygen, which allows your cells to function.

2. Brain function

Your brain is about 73 percent water. Research shows that being just 2 percent low on water might make it harder to focus and can have a negative effect on your mood.

Dehydration can also lead to brain pain. Lack of fluids can trigger headaches or make them worse. Thankfully, drinking a tall glass of water will typically ease discomfort within a few hours.

3. Regulated body temp

Staying hydrated keeps your body temp in check. When you start to get physically hot or emotionally agitated, blood circulates at a higher rate near your skin. That’s why some people get flushed when they’re arguing.

Drinking ample amounts of water will help you sweat, which reduces body heat.

4. Healthy digestion

You might’ve heard that drinking water with a meal can mess with digestion. But it’s actually the opposite!

Water is a major part of saliva, which helps break down food into smaller pieces. This helps the nom noms get to your stomach more easily. Once the food is in your stomach, water helps the digestive enzymes break it down even more.

5. Energy and performance

According to the “The Waterboy,” water can turn you into a finely tuned athletic machine. There’s some truth to that, since fatigue is a common symptom of dehydration.

Dehydration can decrease your overall blood volume and reduce the amount of blood that gets to your brain. That’s why you might feel fuzzy, foggy, or sick if you forget to bring your water bottle to the gym.

Water is also key for keeping your muscles functioning at their best. Research shows that even mild dehydration can zap your muscle strength, endurance, and anaerobic power. To make the most of your workout, chug-a-lug.

6. Slay that sleep

H2O keeps the tissues in your mouth, nose, and throat from getting dry. Waking up with an itchy throat throughout the night is annoying AF. Dehydration can also lead to nighttime leg cramps that mess with your sleep schedule.

Guzzling tons of water right before bed can lead to unwelcome wake-up calls from your bladder. To reap the snooze-promoting benefits, spread your water intake evenly throughout the day instead of chugging before bed.

7. Keep that breath fresh

Spit plays an important role in your overall health. It flushes away debris from food and neutralizes acids from plaque.

Saliva is mostly made of water, along with other components like enzymes, electrolytes, and mucus. Without it, food bacteria would build up throughout the day and start to make your breath smell less-than-fresh.

It’s no wonder one of the common symptoms of dry mouth is bad breath. Yuck.

8. Healthy joints

Just like your body needs water to make blood and saliva, it needs water to produce synovial fluid. This egg white-like fluid hangs out around your joints, keeping them lubricated and staving off painful friction when you move around.

9. Healthy 💩

Water keeps food moving through your digestive tract at a steady clip and makes poop softer. This can help you, um, go a little more easily. Drinking water regularly can also reduce your risk of bloating and constipation.

10. Kidney flush

One of your kidneys’ main jobs is to filter out waste from your bloodstream and turn it into urine. Water is vital to keep that filtration process running smoothly.

Consistently falling short on water can cause your urine to become more concentrated (and smelly). It can also lead to painful kidney stones.

11. Weight management

H2O plays a key role in keeping your metabolism humming along. In fact, according to a 2003 study, guzzling a big glass (specifically 16 ounces) can boost your metabolic rate by 30 percent. It can also increase calorie burning for up to 40 minutes.

If you’re trying to trim some pounds, drink water before your meals. Water fills up your stomach, leaving less space for food. This could explain why in a 2010 study, adults with overweight or obesity who drank 16 ounces of water before meals lost 44 percent more weight than those who didn’t.

12. Blood pressure

People who are chronically dehydrated tend to have higher blood pressure. Running low on the wet stuff prompts your brain to signal a release of the hormone vasopressin.

Vasopressin is an antidiuretic, meaning it tries to get your body to hold on to as much precious liquid as possible. But it also causes your blood vessels to constrict, which can send your BP up.

13. Stay wet, stay beautiful

Talk about the fountain of youth! Your skin is made up of about 30 percent water. This helps your skin maintain its plumpness and elasticity. Staying hydrated can also improve your skin’s thickness and texture while bringing a dull complexion back to life.

You’ve probably heard that you should shoot for eight glasses of water a day. But that rec isn’t rooted in a whole lot of science. The truth is that you likely need a little more — but how much more depends on a bunch of factors.

How much is enough?

Total:
The National Institute of Medicine suggests that men should get about 125 ounces of total water daily. Women should aim for 91 ounces.

Drinking:
About 20 percent of water intake comes from food. So men should drink about 100 ounces of water daily, and women should drink about 72 ounces.

Keep in mind, that’s only a rough estimate. Your needs might be higher if:

  • you’re very active
  • you have a higher body weight
  • you spend a lot of time outdoors
  • you live in a hot climate
  • you’re pregnant or breastfeeding

You don’t have to obsessively track your water intake. You’re probably fine. Just be sure to pay attention to how you feel.

If you’re rarely thirsty and your pee is clear or pale yellow, you’re probably drinking enough water. If you’re frequently thirsty or if your urine is dark yellow, it’s time to start sipping.

So listen to your body and drink up! 💦