Summer is here and as the weather heats up, we spend more time outdoors. Staying properly hydrated as the temperature rises becomes a more relevant concern. Water makes up as much as 60 percent of an adult body weight and performs crucial roles such as carrying nutrients and waste products between our major organs, helping regulate temperature, lubricating our joints and acting as a shock absorber. However, some myths about how much hydration you really need and the correct way to consume it continue to cause confusion. The latest guidelines prove there’s no need to guzzle down gallons of water daily.
Proper hydration is nothing to roll your eyes at. Even being mildly dehydrated can cause side effects such an irritability, headaches, and feeling sluggish. Angie Eakin, MD, a family medicine physician at Barnard Medical Center in Washington, D.C. says, “Every single cell in your body needs fluid to function properly.” On the other hand, a lot of conventional guidelines are really outdated myths. We set the truth to some of the most falsely repeated ones below.
The 8X8 rule is for everyone
You can throw this one out with the bath water. The 8x8 rule (drinking eight, eight ounce glasses of water) originated from an outdated recommendation from 1945. It was based on a dietary suggestion from the Food and Nutrition Board (now the Institute of Medicine or IOM), not taking into account that other liquids as well as foods consumed make up our daily quota for hydration.
The new guidelines released in February 2004 advise healthy adults to use thirst to determine their fluid needs. Survey data from an IOM report loosely recommends 91 ounces for healthy women (11 cups/daily) and 125 ounces for healthy men (15 cups/daily). If that seems like a lot, remember this takes into account total fluid intake including from food and other beverages besides water. The recommendation is not meant for athletes, pregnant women or those with a medical condition requiring fluid control.
Only water fulfills daily hydration
Any type of liquid (coffee, tea, soda, juice, etc.) contributes to your daily hydration including moisture from food. Barbara Rolls, PhD, a nutrition professor at Pennsylvania State University says moisture from food accounts for 20 percent of the fluid you need. Her recommendations for some of the highest-content water foods include: spinach and strawberries (91 percent water), cauliflower (92 percent water) and cucumbers (97 percent water).
As for mistaking thirst for hunger, Rolls says it’s not possible. “The sensations for thirst and hunger feel different and are regulated by separate mechanisms in your body.” Looking to lose weight by drinking more water? You might be disappointed. While eating foods with higher water content (see examples above) can increase your fullness factor, you can only lose weight if you substitute them for higher-calorie beverages or foods.
You should be drinking all day long
Not so, says Dr. Eakin. “It’s okay to feel a little thirsty. Just don’t wait too long to grab a drink.” Thirst is a normal symptom, and if you have no underlying health issues, not something to worry about unless you start feeling lethargic or feel a headache coming on. Severe symptoms of dehydration are much more serious: extreme thirst with no urination combined with confusion. Those symptoms need to be treated through intravenous fluids you can get from a hospital or emergency room.
Simply follow your thirst cues and you should be fine. If you don’t feel like counting daily ounces of fluid consumed, keep an eye on your urine color. If it’s pale yellow, you’re doing fine. Dark yellow? Drink more!
Exercise requires lots of water!
While it’s true that you lose fluids during a hard workout, there’s no reason to gulp down massive amounts of water during your workout. Mitchell Rosner, MD, professor of medicine at the University of Virginia Health System says there’s no magic number to hit—drink when you’re thirsty. Dr. Rosner, who authored guidelines on water and exercise in the Clinical Journal of Sports Medicine 2015, says if you’re concerned you’re losing too much during your workouts, weigh yourself before and after exercising. For every pound lost, drink 16 ounces of water.
As for those sports drinks becoming so popular at gyms, think of your daily exercise schedule. If you regularly perform high-intensity training lasting over an hour (marathon running, cycling or competitive sports), they may be beneficial for you. If not, stick to water.
On the other hand, there is such a thing as overhydrating, and that can be a much deadlier concern. Hyponatremia occurs when the level of sodium in your blood gets too low. It’s caused by drinking large volumes of fluid, even ones containing electrolytes. Bottom line: listen to your thirst!
Here are some foods with high water content, according to the American Dietetic Association:
| Food | Percentage Water |
|
Lettuce (1½ cup) Watermelon (1½ cup) Broccoli (1½ cup) Grapefruit (1½ cup) Milk (1 cup) Orange juice (3/4 cup) Carrot (1½ cup) Yogurt (1 cup) Apple (one medium) |
95% 92% 91% 91% 89% 88% 87% 85% 84% |