To keep you healthy, your immune system relies on a well-hydrated body.

Water is the most natural drink on earth – humans, after all, drank water long before they drank tea, beer or wine. So even though drinking a glass of water shouldn’t require a second thought, here’s a reminder of why we need to pay more attention to consuming the world’s oldest beverage.

The human body is nearly 70 percent water, so it’s no surprise that we need to stay well hydrated to stay healthy. You need to drink enough water so that your body can properly digest your food and deliver nutrients to your cells and get rid of substances that your body doesn’t want.

Without enough water, controlling body temperature would be a challenge, your joints would lack lubrication and your muscles would tire more quickly, too. The bottom line is this: every cell, tissue and organ needs water to function properly.

Water and Immunity

Just like every other system in the body, the cells of your immune system require nutrients to do their job. Here are three main ways in which water supports immunity:

Water is essential for nutrient absorption.

Water is needed during the entire digestive process, particularly when it comes to nutrient absorption into the bloodstream. Once there, the nutrients are transported in this watery environment to all the body’s cells, where they can be taken up and utilized.

Water is a key component of lymphatic fluid.

Water is an important component of another important fluid in your immune system, called lymph (or lymphatic fluid), which travels through a separate system of vessels.

The lymphatic fluid contains specialized white blood cells called lymphocytes that help the body fight infection. As the lymphatic fluid circulates, it helps remove waste products, toxins and impurities from your body – including bacteria and viruses. Since your lymph system is about 96 percent water, it should make sense that dehydration could slow down the function of this natural drainage system in your body.

Water helps maintain healthy mucous membranes.

Another way that water and fluids support immunity is by maintaining the health of your mucous membranes. Just as your skin helps to protect the outside of your body from foreign invaders, your moist mucous membranes act as a barrier, too. These membranes protect those areas inside your body that are exposed to air – like your nostrils, mouth and throat. When your body lacks adequate fluid, your nasal passages may become dry, making the barrier less effective.

Lastly, if you have an illness and have been coughing and have a dry throat, or if you have a fever, or if you’ve been losing fluids because of a stomach or intestinal upset, it’s vitally important that you consume plenty of fluids to help your system recover.

6 Tips to Help You Stay Hydrated

If you find it hard to drink enough water every day, here are some tips that might help you.

1. See it.

It can be really helpful if you can see the amount of water you plan to drink and track your progress over the day. Put the amount of water you plan to have in a pitcher on your kitchen counter or keep it at your desk. It will serve as a reminder to drink more, and you’ll be motivated to sip on it as the day goes by – and meet your goal of finishing it.

2. Cool it.

Cold water often seems more refreshing than room-temperature water. Try stashing a bottle of water in your freezer and carry it with you during the day. It will stay cold for several hours, and you might be encouraged to drink more.

3. Wake up to it.

“Morning mouth” is a reminder that most of us are naturally a bit dehydrated in the morning. So keep a glass of water by your bed and drink it first thing – before your feet even hit the floor.

4. Flavor it.

Make your own spa water. Add a slice of fresh lemon or lime, some cucumber, a few berries, some fresh mint or a slice of fresh ginger to your water. It makes it feel special and adds a hint of refreshing flavor.

5. Eat it.

Don’t forget that watery foods like fruits and vegetables (but particularly cucumbers, melons, tomatoes and leafy greens) contribute to your overall daily fluid needs, so include plenty of these healthy foods with meals and snacks.

6. Track it.

Just like keeping track of your calorie intake, keeping track of how much water you drink can help a lot, too. That’s why the pitcher-on-the-desk trick works so well – at any moment, you can see how much water you’ve had and how much you need to drink before the day is over. If you want to go high tech, there are apps for your phone that can send you drinking reminders, keep track of your progress and even give you a virtual pat on the back when you’ve met your goal.