Drinking enough water is one of those annoying health goals that all of us seem to have. Maybe it’s because we know it’s healthy to stay super hydrated, but whenever we increase our water intake we just end up peeing every five seconds. So what gives? How much water should you drink a day? And how can you tell if your daily water intake is enough? Let’s get into it.
This is how much water you should drink a day, according to experts.
You've probably heard you're supposed to drink at least eight 8-ounce glasses of water daily. That's almost enough to fill a 2 liter bottle—which even the most diligent water-drinkers may find daunting. But that classic advice can be a little misleading.
"Fluid requirements vary among individuals based on age, sex, activity level, and even where you live," Jessica Fishman Levinson, M.S., R.D., C.D.N., founder of nutrition counseling company Nutritioulicious tells SELF. So, how much water you should drink a day may actually vary each day, depending on the other things you're doing, eating, and drinking.
The Institute of Medicine actually recommends that women get 2.7 liters—that’s 11 cups—of water per day. But here’s the thing: They don’t say you need to drink 11 cups of water a day.
What counts towards your daily water intake?
All fluids count toward your daily intake, not just plain old H20. That includes all sources of water—from a basic glass of tap, to a cup of coffee, to the water content of the foods you eat (which, the IOM estimates, makes up about one-fifth of your daily fluid intake). If you listen to your body—drink when you’re thirsty, eat when you’re hungry—chances are you’re going to get what you need, or pretty close to it. So stop sweating the eight glasses a day hubbub and think about it this way instead.
According to the Mayo Clinic, the benchmark should really say "eight 8-ounce glasses of fluid," not water, because drinking things like milk, tea, and juice contribute to your total. "Good options for hydration without added calories are waters infused with fruit and herbs, unsweetened tea, and sparkling water," Levinson says.
Your diet can affect your daily water intake, too.
"Your body absorbs water in foods just like it would liquids," Levinson says. Many fruits and vegetables have high water content. Some good options: watermelon (duh), cucumbers, lettuce, celery, tomatoes,strawberries, oranges, and grapefruit. Even soup, Jell-O, and ice pops count as fluid.
But some foods and drinks can increase how much water you need. "Foods with a diuretic effect, such as alcohol and asparagus, may cause you to excrete more water so you may need more," Levinson says. If you eat high-sodium foods, your body likely will retain more water, leaving you thirstier. Drinking more fluids will help dilute your system and get fluids moving regularly again.
So, how can you tell if your water consumption is good enough?
Since you're not always keeping track of these sneaky sources of fluids, the best way to gauge your daily water intake is by how your body feels.
If you're thirsty, your body's telling you that you need more water. "You might already be dehydrated," Levinson says. Another good way to determine your fluid status is by taking a peek inside the toilet after you pee. "If your urine is light yellow, you're probably getting enough fluids. If it's dark or smells strongly, you probably need more water."
It's also important to make a conscious effort to drink more whenever you're getting sweaty. Along with food, water is the fuel that powers your workouts. As you sweat, you're literally losing water, and you have to replenish it as you go. Aim to drink one or two cups of water before you exercise, and sip about a half to one cup of water every 15 minutes while you're working out. If you're sweating really hard, or if you're out in the heat, you might need more—listen to your body.
You don't need to obsess about hitting a particular number of cups/liters/gallons/bottles of water each day, but it can be helpful to get in the habit of drinking more regularly throughout the day. To make sure you're hydrated, keep a refillable water bottle with you all day so you can constantly sip whenever you want. For more tips, check out these 12 easy ways to drink more water every day.
Here are some subtle signs of dehydration that may mean you need to increase your daily water intake:
Some of the signs of dehydration are fairly obvious—but others aren't. If you're thirsty, you should drink. That's a no-brainer. But there are a few other signs of dehydration that aren’t as obvious.
- You’re feeling hungrier than usual. Thirst and hunger cues come from the same part of the brain, so it's easy to confuse the two. If you feel hungry even when you know you've eaten enough, there's a good chance your body's actually telling you it needs water, not food.
- You’re feeling super dry. When your body is begging for hydration, the need can manifest in various signs of dryness, including dry mouth, chapped lips, dry skin, and a lack of tears.
- You have a headache. Doctors aren't quite sure why, but they think it might be because when hydration levels drop, so does blood volume, which can reduce oxygen supply to the brain.
- Your muscles feel weak or crampy. Cramping, muscle spasms, and generally feeling weak or fatigued can all be indications of dehydration.
- Your breath is randomly stinky. Having bad breath can be a tip-off that you need to sip some water. That goes with the dry mouth thing: Saliva has bacteria-fighting properties; when your saliva levels go down so does your mouth’s ability to fight odor-causing germs.
In addition to all that, rapid heartbeat or breathing, sunken eyes, fever, confusion, or delirium can all be signs of severe dehydration. If you have these symptoms, seek medical attention.
We know you’re wondering: Can drinking more water help you lose weight?
While drinking more water won’t actually cause you to lose weight, there is usually a relationship between how much water you drink a day and how much you’re eating each day. That’s because hunger can actually be a sign of thirst.
As we mentioned, thirst and hunger cues are easy to confuse, so if you’re feeling famished even though you know you aren’t, it might be that your body really needs some water. So, in this case, if you’re not drinking enough water, you may be more likely to mindlessly snack throughout the day. While drinking more water shouldn’t be seen as the secret to weight loss, it certainly can’t hurt to increase your daily water intake.
By the way, it is possible to overhydrate, especially during endurance activities, like running a marathon.
Marc Leavey, M.D., an internist at Baltimore's Mercy Medical Center, previously told SELF: "There are a scattering of cases [of overhydration] seen among athletes, runners, and those exercising and trying to consume extra water." Overhydration can cause a condition known as hyponatremia, which happens when the sodium levels in your bloodstream become unusually low, leading to your cells becoming waterlogged. Signs include feeling nauseated, confused, run-down, and irritable. Overhydration can also cause seizures and put you into a coma if it’s not caught in time.
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