Thank you for signing up!
Is Drinking 8 Glasses of Water Enough?
You get a fountain of answers when asking nutrition experts whether we need to drink the oft-advised eight glasses of water each day: Eight is enough or not enough or more than enough or not even the right question.
“The research question has been raised whether there is actually scientific evidence for drinking eight to 10 glasses of water each day,” said JoAnn Hattner, a clinical nutrition professor at Stanford University.
The best answer about eight glasses? A resounding, “It depends.”
For instance, a good number of nutritionists suggest we need a varying amount of water based on body weight. A common recommendation is to divide your weight in half and that’s the number of ounces you need each day.
Sports nutritionists will chime in, “Not so fast.” They recommend adding back 10 ounces for every half hour of daily exercise. That totals to 85 ounces a day for a 130-pound woman who takes an hour-long yoga or Pilates class. If she skips the class, then roughly a half-gallon of water will suffice.
Nutritionists agree the body needs water and fluids for optimal health. Making a point to drink water throughout the day will produce such happy results as feeling more energetic and less hungry. Water flushes toxins out of the body and keeps your organs functioning at peak levels.
To be more savvy about water consumption is to be a sipper rather than a guzzler. Here’s the problem with guzzling: If you drink too much fluid at once—say, two or three glasses in the morning—you can overload the kidneys without actually hydrating the body.
A healthier strategy is to consume eight ounces every one to two hours (a particularly good idea if you are constipated). Hydration through sipping helps the body do things like deliver an adequate blood supply to the skin.
“It’s always better to space it out,” confirmed Monique Ryan, a Chicago-area nutritionist based in Evanston.
One major bonus of spacing out your water intake: Fewer bathroom runs.
There is no exact healthy number of bathroom breaks in a day; it varies as much as our names or even fingerprints. But going more than three hours without a bathroom break during daytime hours likely means you are not drinking enough water.
On the other hand, awaking to urinate twice or more during sleep indicates you need to seek a health practitioner’s attention. Overnight frequency, especially at younger adult ages, is not to be taken lightly.
Things are more fluid
While eight glasses of water has been a standard goal for decades—some people “credit” the tally from the popular Dr. Stillman Diet of the 1970s—a new and welcome wrinkle is the range of beverages that nutritionists now count toward your daily hydration total.
“What’s really changed is that caffeine is not considered as severely dehydrating,” said Ryan, author of the book Sports Nutrition for Endurance Athletes (Velo Press). “Caffeinated drinks can count as about half water.”
That means your 16-ounce morning coffee can count as one of the recommended eight to 10 cups of water. Or half of your soda is equal to six ounces of water. It appears caffeine itself is not the diuretic agent once believed, though it does prompt most people to urinate more frequently. The result is 50 percent fluid loss.
One caveat: Some people, if they are honest about it, likely lose most of that coffee and then some to agitated bladders. They may find that drinking espresso without the milk of a latte or water of an Americano-style cuts down on personal fluid loss.
In any case, Ryan was quick to add that this reversal of thinking is “not a directive to drink caffeine.”
And certainly no practitioner recommends the excess sugar (10 teaspoons per 12-ounce serving) of regular soda or additives of diet soda.
Some consumers say they prefer soda to water because soda is colder and more refreshing than a room-temperature bottled water. One idea is to look for the newer water bottles with cores that can be frozen and then inserted to keep the water cool all day. While conclusive research proves elusive, preliminary studies show people who drink cold water will burn an extra hundred calories or so compared to individuals who consume the same amount of room-temperature water.
Carbonated drinks often hit the spot, but rather than pushing the cola button on a vending machine, consider a sparkling water with a splash of juice or fresh-squeezed lemon, lime or orange.
Equal to water
Jackie Berning, assistant professor of nutrition at the University of Colorado at Colorado Springs and nutritionist for several Denver-area professional sports teams, said she tells her athlete-clients that beverages such as juice, milk, soy milk and herbal teas can match water, ounce for hydrating ounce. She and other nutritionists mention provisos about juice (drink 100 percent varieties, consume only 6 to 8 ounces daily because of high caloric content, don’t use it to quench thirst) and various milks (require more work in the digestive tract than water).
A notable exception is beer, wine and other alcoholic drinks, which don’t count in the hydrating column. Research shows alcohol blocks a hormone that otherwise helps the body stay hydrated. In fact, a frequent suggestion is to consume a full glass of water for every alcoholic serving.
Ryan cautioned that consuming alcohol after exercise may also inhibit muscle recovery.
So much for the post-workout beer? Your choice, but you might reconsider having more than one.
Ultimately, each of us needs to get in the flow of our personal health and energy levels.
“You are the best judge of whether you are getting enough fluids in your day,” Hattner said. “It’s more than monitoring your thirst, [which actually becomes less reliable as a hydration alert in adulthood, compared to grade-school and teenage years]. If you are feeling lethargic, it may well be from lack of hydration.”
Let’s all drink to that, whether it adds up to eight glasses of water each day or not.
Andrew Mulholland never drinks his water from a soft pliable plastic bottle if he can help it.