How much water should you drink a day? Forget the simple math—eight glasses a day isn’t the answer. And forget the complicated math, too—half your body weight in ounces isn’t right, either. In fact, there’s no formula that gives you the magic number for daily water intake or hydration. “It’s really dependent on your individual needs,” said Tyler Florek, a registered dietitian nutritionist at Banner Del E Webb Medical Center in Sun City West, AZ.
How many calories you eat, how much you weigh, how much physical activity you do and what health conditions you have, including if you are pregnant or breastfeeding, all play into the amount of water you need to drink. Florek said that instead of measuring ounces or glasses of water, look to your urine to tell if you’re drinking enough. Your urine should be pale yellow and almost odorless. Dark yellow urine with a strong odor are signs of dehydration. If you aren’t drinking enough water, you might also notice signs such as fatigue or headaches.
You don’t want to overdo it with water, either. Drinking more than about a liter of water per hour for several hours can cause water intoxication, where your electrolytes get out of balance. It can cause headaches, nausea, and vomiting, and in extreme cases it can be fatal.
What’s the big deal with drinking water?
More than half of your body is made of water, and water is crucial to just about everything your body does. What it does:
- Keeps all your organs functioning properly
- Maintains your blood pressure
- Helps your kidneys filter your blood
- Helps you excrete toxins and waste through urination
- Lubricates your joints
Can drinking water help you lose weight?
“Water itself doesn’t have any special weight loss properties,” Florek said. But if you replace high-calorie, sugar-sweetened beverages with water you could see some weight loss. Florek recommends choosing water as your main beverage as much as possible.
Don’t waste your money on things like alkaline water bottles, though. “Your stomach has a way of strictly managing the pH of foods and drinks you consume. So as soon as you drink alkaline water, your body neutralizes it. There is no scientifically proven benefit to drinking alkaline water,” he said.
And it’s a myth that caffeinated beverages dehydrate you. They may make you need to urinate, but you won’t expel more water than you took in. Water is still the best choice, though.
The bottom line
“Drinking enough water seems to be a struggle for a lot of people. But at the end of the day there is no getting around the fact that getting enough water is absolutely vital to your health,” Florek said. There are lots of ways to get creative about how you stay hydrated. Find what works for you.”