Water has gone beyond simply being good for us: reusable water bottles have become a statement unto themselves, signalling our health- and environmental-consciousness to the world. We’re so conditioned to constantly guzzle water that some people panic if they don’t have it on their person at all times. But how much water do we actually need to drive every day? We spoke with a doctor to find out.
While a lot of people may disagree about the exact amount of water you should drink each day, we do know that our needs differ depending on our body type, how active we are, our diets and other health factors. Because there’s no specific measurement that will fit all people, I consulted Dr. Pamila Brar, an internist with more than 20 years of experience, to get some basic guidelines. She suggested the following, presuming you live in a temperate climate:
Men should drink about three litres (about 13 cups) of total fluids a day
Women should drink about 2.2 litres (about nine cups) of total fluids a day
This is just a baseline, of course. If you exercise, spend time in hot or dry weather, you consume a significant amount of diuretics (e.g. caffeinated drinks like soft drink), or your medications require additional water consumption, you may need more water. The easiest way to handle your water consumption is to stick with the baseline above and add more water whenever you feel thirsty.
How can I make sure I get enough water?
Presuming you’re awake for approximately 16 hours per day, you’ll have to drink between 130mL and 180mL per hour. That may seem like a lot, but it isn’t much more than four to eight sips per hour (depending on how much you take in). If you always have water with you and have an easy method of refilling (e.g. sink, water cooler, etc.) you won’t have too much trouble.
Also, don’t forget that many foods contain water, and that counts too. Per Lifehacker health editor, Beth Skwarecki:
We get roughly half of our daily water intake as food: watermelon and soup are more than 90% water, as you may have guessed, but even a cheeseburger is 42%. We also get water from other drinks like soda and coffee, even if they have caffeine. (While caffeine can act as a diuretic, your body adapts to that effect over time.)
Aside from remembering, many people don’t drink enough water because they don’t like the taste. Sometimes this is a problem with tap water more than water itself, so consider a water cooler for your home if you hate the taste of tap water, don’t like the negative environmental impact of bottled water, or want to pay much for the vital beverage. If that’s not the problem, there are many ways you can augment water’s natural flavour to help you enjoy it more. And don’t forget: foods and beverages other than actual water count towards your daily intake.
Can I drink too much water?
You can have too much of anything, but you’ll find it challenging to have too much water. Dr. Brar explains:
In a healthy adult, the kidneys can filter and excrete 15 litres of water a day. So you are unlikely to get too much water, provided you don’t drink an enormous amount at one time. Just remember to pay attention to thirst cues, try to anticipate when activities or the weather might increase your need for water, and carry water with you always.
For most of us, too little water is more of a problem than too much. Drinking 15 litres of water each day would not only take quite some time but make you feel very uncomfortable. There are really no circumstances where you’d accidentally drink too much water (aside from drowning/water accident situations), so drinking more than you need is a safer bet than drinking too little.
What happens if I don’t get enough water?
While more water than you need is unlikely to hurt you, too little water can cause all sorts of problems. Water aids in digestion, makes your skin look healthier, helps you feel more full so you don’t overeat, keeps your kidneys healthy (so they can properly flush out toxins) and contributes to regular healthy bowel movements. You lose out on those benefits if you don’t stay hydrated. Additionally, dehydration makes you feel tired and fatigued. Dr. Brar explains why:
Dehydration makes you feel tired. The right amount of water will help your heart pump your blood more effectively, and water can help your blood transport oxygen and other essential nutrients to your cells. Water also helps energise your muscles and prevents cramping. This is especially important if you find yourself tired at the gym. You should drink two cups of water about two hours before you exercise.
Water won’t just help you stay more awake and alert during the day, but also reduce fatigue during sports and exercise. While the benefits it provides are important, this is one benefit that’s especially relevant to those who work often and for long hours (especially when caffeine’s thrown into the mix).
Ultimately, you can get by without sufficient water but you won’t feel good. While it may be tough at first to drink as much as you need, practice will help you form good hydration habits that will lead to better overall health. Getting more water throughout the day is a good opportunity to stand up and walk around so you’re not sitting or going without a break for too long. It’s no surprise that water is good for you, but the benefits of sufficient hydration are many and well worth the trouble.
This story was originally published in 2013 and was updated on 12/5/19 to provide more thorough and current information.