You need different amounts of water depending on your situation and environment. If you pay attention, your body will tell you whether or not you’re hydrating properly.
Read on to learn what Thayer White, M.D., a Providence sports medicine doctor in Portland, Ore., says about the factors—urine color, air travel, sweating, to name a few—that influence how much water you should be drinking.
Q: How does weather affect hydration?
How much water you need to stay hydrated depends on heat and humidity. When it’s hot or less humid, you lose more water. Skin is pretty good at keeping water in, but dry air is going to dry you out faster. Every time you breathe, a little water vapor leaves the body. You’re still losing water even if you aren’t sweating.
Q: We know “eight glasses of water a day” is a myth. How much water should we be drinking?
Most of what I’m going to say applies to healthy people. If you have a heart or kidney condition, check with your doctor. For folks who are otherwise healthy, the most important thing to pay attention to is thirst. If you’re thirsty, drink more—the best thing to drink is plain water.
Pay attention to urine production. On average, you should be urinating every few hours and the urine should be light. If urine is dark or infrequent, drink more water. (Some medications and medical conditions can darken urine.) Generally speaking, dark yellow urine is a sign of dehydration. Brown or red urine may be a problem that needs to be checked out.
What I want to emphasize is to drink according to thirst. It can (rarely) be dangerous to drink too much. Drinking large amounts of water, if you do not need to, can cause an imbalance of electrolytes.
Q: By the time you’re thirsty, do you need to drink extra to catch up?
No. When you’re thirsty you should drink enough so that you’re not thirsty anymore. Your body is very sensitive to concentrations of electrolytes and amount of fluids in the body. It will tell you if you’re thirsty; you don’t need to over-drink.
Q: What about sweating?
If you are sweating, you do need to drink water to compensate for the moisture leaving your body in addition to the amount of water you would normally drink.
It’s a sign of dehydration if you haven’t urinated in, say, six hours. What you need to be concerned about is how much water is staying inside the body, in your cells and organs. That will regulate how much urine you make. If you’re sweating, you probably will not make as much urine.
Q: Can hydration come from sources other than water?
Lot of foods contain water—that counts toward fluid consumption.
Liquids are pretty equivalent. It’s fine to drink unsweetened tea or black coffee, but water is the healthiest and cheapest. You’ll get the same hydration benefits for an equal volume of water or soda. But soda has lots of sugar and calories.
Q: When is it appropriate to drink a beverage with added electrolytes?
For most people who are looking to drink something and stay hydrated, plain water is best. Waters with added electrolytes like Smartwater aren’t providing an additional benefit and will certainly cost more, but there’s no harm in them. Sports drinks like Gatorade and Powerade are best for people participating in high-intensity or hot weather sports. They contain a fair amount of sugar, which is not what most people need. If you’re actively burning calories and need energy during a sport like basketball or running, a sports beverage is fine.
Q: Does air travel increase the likelihood of dehydration?
The air on planes is drier and less humid because of altitude. Drink more water to keep from getting dehydrated, especially on a cross-country or long flight. Try to avoid caffeine or alcohol, which can act as a mild diuretic.
Q: Why is it important to hydrate after getting a massage?
A deep massage increases circulation and helps breaks down scar tissue, which releases toxins. Water helps flush out the toxins.
Talk to your primary care provider if you have questions about hydration. Don’t have one? You can find a Providence provider here.
