Newsflash: Your body needs water to survive.
Okay, we’re just kidding. That’s not exactly news.
We all know that water is one of our most pressing physiological needs – along with food, oxygen, and sleep – and you’ve probably even heard that your body is composed of 60% water.
That part is obvious. What’s not so obvious, apparently, is how much water we should drink per day to stay healthy. Unfortunately, there’s a lot of false and misguided information out there on this topic.
No big deal, right? Wrong. Because while dehydration is bad, over-hydration is bad too. It can make you sick – or literally kill you. Not to mention the bloating and constant whizzing.
Without further ado, let’s blow the bad info out of the water (pun intended), and then figure out how much water we really need.
One of the most widely pushed claims about water requirements is that we need at least 8 glasses of 8 oz of water per day.
For years, folks have been carrying around their water bottles everywhere they go, trying to get their “8 glasses”. Many of these people aren’t sweating much, and in fact spend the majority of their day in their air-conditioned office or home.
But we’re here to tell you that the 8 glasses per day rule is just plain wrong. There is no scientific evidence whatsoever to suggest the average, largely sedentary person needs to drink at least 64 oz of water every 24 hours.
The proponents of the 8 glasses myth also claim that other beverages, like coffee, tea, and soft drinks, don’t count towards your daily water requirements. In fact, they say these caffeinated thirst quenchers are a net negative, since they’re diuretics that actually dehydrate rather than hydrate you.
This is also wrong. Adding coffee grounds or tea leaves to life-giving water doesn’t magically make it dehydrate you. And milk, juice, and many other non-caffeinated drinks are mostly water as well.
Coffee and other caffeinated drinks are mild diuretics – but only when you rarely consume caffeine. For regular coffee and tea drinkers, your body adjusts to the point that it has little to no diuretic effect.
In short, yes, coffee, tea, milk, juice, and even soft drinks contribute to your daily water requirements. Even alcohol does to a degree, when not consumed in excess.
Want your mind blown even more? Roughly 20% of our daily water requirements come from the food we eat.
So, to summarize:
Now, please, for the love of health, let this myth die already. Agreed? Good.
Okay, so now that we’ve shown that you don’t really need as much water as some claim, how much do you need?
In short, there aren’t any hard, set numbers. If you…
You’ll need more water. If you have a smaller body type and spend most of your day indoors, you’ll need less. Of course, certain medical conditions could also influence your necessary water intake, as can your diet and any supplements you take.
But here’s the thing. Your body is evolved to tell you how much to drink.
When your body wants water, it tells you. That’s what thirst is. When you’ve had enough water, your body will again let you know by making it difficult to swallow.
The final myth that we have to dispel is the notion that by the time you feel thirsty, it’s already “too late” – and that you should actually drink before you’re thirsty.
This is simply not true. The reason you feel uncomfortable and have difficulty forcing more water down when you’re not thirsty is because your body is saying, “Uh, hey? We’ve had enough, can you cut it out? No, seriously, dude/lady, stop it.”
Now, there may be times where you want to hydrate a little preemptively – right before a session of strenuous exercise, for example – but in general, you should drink when you are thirsty.
Fortunately, your body, the well-built organism that it is, provides yet another way of gauging your hydration levels: the color of your urine.
When you drink a lot of fluids and are well-hydrated, your urine is lighter or even clear. If your urine is dark, you’re dehydrated and need to drink more. Being properly hydrated also means you’ll have to pee more, which means more urine to inspect.
To sum it up, here’s how to make sure you’re getting enough water:
Pretty crazy, eh? Modern scientific research has confirmed what humans knew back when we were living in caves.
One of the biggest problems with the recommendations to drink over 8 glasses of water and its accompanying command to drink when you’re not thirsty is that over-hydration is actually dangerous.
This is known as hyponatremia. The excess water causes your sodium levels to drop which in turn causes your brain to swell, to the point that it’s pressing against the inside of your skull, leading to lack of mental clarity or confusion, loss of consciousness, seizures, and even death.
Yes, you can friggin’ die from drinking too much water. It has happened before, and unfortunately it will likely happen again.
In 2002, a study of Boston Marathon runners found that 13% had hyponatremia – and 0.6% had severe hyponatremia. That same year, one participant collapsed during the race and died two days later from it.
Yes, people who do strenuous activity, like during marathons or in Army basic training, should drink more water. But over-hydration is all too common in both groups.
If you’re not running a marathon or attending military boot camp, what should that tell you about your water consumption?
As we’ve shown, most people don’t actually need 8 glasses of water per day, and actual requirements will vary depending on the person, their physiology, and activity level.
So, while hydration is very important to both our survival and our optimal functioning as human beings, we should be careful not to overdo it.
Your body is designed to tell you when you’re hydrated, so follow its cues. Drink when you’re thirsty, and don’t force excess fluids down the hatch. Pay attention to your urine color and what it tells you about your hydration levels. And keep in mind that your morning coffee or orange juice, evening glass of wine, and much of the food you eat contributes to your water levels.
In short, don’t overthink it. You don’t need to measure every ounce you drink or drown yourself in water to crush your fitness goals.