When astronomers look through their telescopes for life elsewhere in the universe, they’re mostly looking for planets that might have water. Without it, life—at least, as we know it—simply can’t exist.

What goes for planets goes even more so for our bodies. Water is the vehicle that carries necessary stuff like oxygen and fuel to all our cells and helps flush out byproducts our bodies need to get rid of. Water lubricates and cushions our joints and helps keep our temperature in that happy zone where the body works right. It makes up the chemical soup by which our nerves send one another signals.

For all these functions to take place, we must constantly renew our body’s supply of water. But how much do we need, and how should we get it? Here’s everything you need to know about this vital life essential.

Water is the building block of life as we know it, and you should be proactive about keeping yourself hydrated even when you aren’t training or being active. The Mayo Clinic has found that an average daily water intake for a man is about three liters. But hydration isn’t the only benefit you’ll experience from drinking that much—your general health should improve as well. Here’s how:

Water consumption helps you tolerate more pain.

Dismissing water from your daily diet can lead to some obvious conditions like fatigue, but have you heard of this one yet? That’s right, according to research published in the journal Psychophysiology, gulping down the liquid beverage can actually help sustain your tolerance to pain. For the study, 17 healthy male participants were put through two tests: one in which they regularly consumed the clear liquid, and the second which required neglecting the beverage for 24 hours. After each test, the researchers dunked the participants’’ feet in ice-cold water (0-3°) for a maximum of four minutes. They discovered that when the males were in the “dehydrated state,” their inclination to yank away their toes was far greater than when they were fully fueled with water. Meaning: Their perception and sensitivity to pain was significantly higher when deprived of water. Consider the tactic next time you try recovering with an ice bath. Or better yet, up your H2O intake in general. I mean, who wouldn’t want to tough out pain more than the next guy?

 Water helps you maintain normal body function.

Research has shown that water speeds up your metabolism, cleans the body of toxins, and generally helps to make everything in your body run smoothly. Considering an adult male is usually 60% water, this all makes sense. You need that water to digest food, circulate blood, keep your mouth from drying out, and do a number of other things we often take for granted. Don’t wait until you’re thirsty—be proactive about it.

 Water can make you feel better in everyday life. 

Scientists from the University of Maastricht in the Netherlands found that patients who suffered from severe headaches and migraines enjoyed an improved quality of life by drinking about seven glasses of water a day. Drink up and stay healthy.

 Water will reduce your cravings for empty calories. 

Some studies have shown that people confuse hunger with dehydration; others find that people eat less if they’re vigilant water-drinkers. Water won’t keep you from eating the food you need to be healthy, but it could help you stay away from the unnecessary junk food your body craves.

 Water increases your energy level. 

In general, dehydration leads to fatigue, which slowly eats away at the bodily functions you need to get through the day. The more water you drink, the more awake and alert you’ll feel. Also, opting for drinking water with a high pH such as Icelandic Glacial [8.4 pH] helps the body detoxify and balance out acidity levels—resulting in better prevention of disease and illness.

 Water is almost always your healthiest drink option. 

A lot of popular beverage choices out there have no nutritional benefits. Soda is mostly liquefied sugar, and a lot of juices are surprisingly in the same boat. Alcoholic beverages should be enjoyed only in moderation, and sports drinks are really only a good choice when you’re in the middle of some intense activity. In most cases, if you’re going to buy a drink, water is your best choice.

 Water keeps your brain firing. 

Water helps the brain make electrical energy to keep synapses firing, nerves sparking, and glands producing hormones (like testosterone).

 Water empowers your muscles.

It gives you the “pump” you feel when you lift, but water also keeps muscles strong. Even a tiny—1.5%—decrease in hydration can lead to strength loss.

 Water aids your liver.

Water thins the blood so it’s easier for the liver to filter out potentially harmful substances—alcohol, drugs, germs, pollutants—that could poison your body.

 Water saves your skin.

Deprived of H2O, skin becomes tight, dry, and wrinkled, and develops cracks in cell walls that can let in infections.

 Water mobilizes your small intestine.

Like an internal garden hose, the small intestine sends water around the body to deliver molecules—amino acids, sugars, fats—your cells need to live.

 *Extra takeaway: Bottled water vs. tap water.

Now that you know it’s important to keep up with your water intake, what about tap water vs. bottled water? Well, not only is bottled water a bit more convenient, but it might also be safer. In a recent study from the Environment Science and Technology, researchers found possible risks of acute gastrointestinal illness from aging water distribution systems. Why risk cramps and discomfort when it can all be avoided with purified, bottled water?