When the temperature heats up outside, you’re probably more acutely aware of how thirsty (and sweaty!) you are. But dehydration doesn’t just strike during the summer months. In fact, you might be dehydrated right now—without even knowing it.
Humans are made mostly of water. 75 percent of an infant’s body weight comes from water, while older adults are made up of about 55 percent, according to research published in the journal Nutrition Review. So it’s no wonder that we need water to live and feel good.
Everyone’s aiming for those eight cups a day, but it’s more individual than that: “For water intake, you ideally should divide your weight in two and drink that many ounces of water over the course of a day,” says Jack Dybis, DO, founder of IVme Wellness + Performance in Chicago, Illinois. “So, a 140-pound woman should drink 70 ounces of water. For reference, 1 liter is equal to 33.8 ounces, so our subject should be drinking a little over 2 liters a day.”
Unfortunately, according to the CDC’s findings, most of us are falling short. In fact, up to 75 percent of Americans are chronically dehydrated.
“Adequate hydration is crucial for basically every element of living,” says Brooke Alpert, RD, CDN. “We can go longer without food than we can go without water. Dehydration can lead to everything from fatigue, weight gain, blood sugar issues, cognitive functioning problems, muscle cramps, or even more serious complications.”
Related: Stock up on water for summertime.
Here are five crucial things you should know about dehydration so you can avoid the short- and long-term effects of it.
1. Watch out for red flags that signal dehydration.
“Everyone needs to be aware of the early signs of dehydration, which include lightheadedness, sore or dry throat, excess sweating, or nausea,” says Matt Tannenberg, a sports chiropractor and Certified Strength and Conditioning Specialist (CSCS) in Phoenix, Arizona. “Later signs of dehydration including extreme fatigue, fainting, and the chills. When you sweat, you not only lose water from your body, but also your electrolytes.” (Your body needs electrolytes because they control cell membrane stability and carry electrical charge.) Older people tend to get dehydrated more quickly as well, so be aware of drinking enough even when you’re not feeling thirsty.
2. There are simple ways to stay on track and make sure you’re drinking enough.
“I find that for my clients who tend to slack off on their hydration, an app like WaterMinder is a great tool to remind them to drink throughout the day,” Alpert notes. “It’s also helpful to get a nice water bottle that you leave in plain sight, which in itself is a reminder to drink.”
Related: Shop electrolyte products, from tablets to drink mixers.
3. if you’re exercising, you’re going to need more water to stay hydrated.
Whether you’re hiking, taking a hot yoga class, or just hanging out on your porch on an 80 degree day, you need to drink more water to make up for all that sweat. Generally, you can add 1.5 to 2.5 cups (or 400-600 milliliters) of water for short bouts of physical activity, according to the Mayo Clinic. If you’re way more active—let’s say you’re running a race— then you’ll have to up your intake based on how much you’re sweating.
4. Your urine can tell you if you’re adequately hydrated.
If you’re rarely thirsty and your urine is colorless or light yellow, your fluid intake is probably adequate, according to the Mayo Clinic. Darker urine can signal dehydration, though.
5. Drink more water, and reap the many benefits.
“Being conscious of your water intake during the day is very important, as hydration has innumerable benefits, like increased energy, headache relief, promotion of weight loss, better skin, hair, and nails and more,” says Dybis.