You know how important hydration is to your athletic performance and overall health, so we're not going to bombard you with more information you already know.
But we will share some interesting new facts about hydration you probably don't know.
Scientists at the universities of Stirling (Scotland), Loughborough (UK), and Bangor (UK) analyzed the hydration potential of different drinks—not just water and its derivatives, but beverages you wouldn't think to be particularly hydrating.
Currently, there's no beverage hydration index (like there is a glycemic index) to help people understand how to optimize the beverages they drink to stay hydrated. Not all drinks hydrate you the same way, and water isn't necessarily the best.
In the study, researchers tested the effects of 13 commonly consumed drinks* on urine output and fluid balance. Seventy-two participants—who had fasted and abstained from any fluids—consumed either one liter of water or one of the 13 other beverages over the span of 30 minutes. Researchers collected urine for the next four hours to monitor body salt balance and establish which fluids were retained in the body for the longest period of time.
“Many people believe that drinking fluids such as tea and coffee causes them to become dehydrated but we found that when drunk in normal amounts and frequency these drinks do not stimulate any additional fluid loss compared to drinking water,” study author Stuart Galloway of the Health and Exercise Sciences Research Group at the University of Stirling said in a press release.
In fact, the researchers discovered several fluids were retained in the body for the same time, or longer, as water. Curious what they might be? Click through our gallery to find out the good, the bad, and the surprising.
*The researchers didn't include so-called "designer waters" like coconut water, but they can be incredibly useful for staying hydrated during the day as well as post-exercise. Read more about coconut water and other great alternatives to tap water here.
“In our trial drinking milk helped people retain a third of the fluid they consumed over a two hour follow-up period and remain hydrated for over four hours," Galloway says. It's actually better than water for rehydration and is more effective at countering dehydration.
Milk and its alternatives is also an amazing recovery drink post-workout because of its natural blend of sodium, carbs, and protein; it can also help your body retain fluids, according to another study published in the journal Applied Physiology, Nutrition, and Metabolism.
Just like milk, rehydration beverages helped people retain a third of the fluid they consumed over a two hour follow-up period and stay hydrated for 4+ hours. If you’re super active, keep an electrolyte replacement drink handy so you can push your limits without hurting your health.
SOS is a great option with 6 times the electrolytes of the average sports drinks, 27 percent more electrolytes than the average coconut drink, and 75 percent less carbs than sports drinks.
Black tea, green tea, chamomile, whatever you like, drink up. Tea has the same hydration effect as water (based on urine output 4 hours after drinking). Plus, there are tons of health benefits thanks to the antioxidants.
As the researchers mentioned, the diuretic effect of coffee doesn't offset its ability to hydrate. Skip the added creamers and sugars when you can. What's more, black coffee gives you an excellent pre-workout jolt.
Fruit and vegetable juice has a water content of 85-100 percent, which is great (veggie juice is higher than fruit on the spectrum because sugar can inhibit hydration). To combat some of the sugar in fruit juice, dilute it with a bit of water. The researchers gave participants orange juice, which contains a high amount of electrolytes. Lemon juice is also a great source. Beet and tart cherry juice also have tons of benefits to athletes; again, just be mindful of the sugar and watch the portion size.
Yep, the researchers didn't leave beer out of the study! The good news is that they found lager has the same hydrating potential as water. But (yes, there's a but!), note that separate research from the International Journal of Sport Nutrition and Exercise Metabolism found heavy, or full-strength, beer can have a dehydrating effect on the body and weaken your recovery and rehydration because of its alcohol and sodium content. That wasn’t the case for low-alcohol (2.3% ABV) beer so choose wisely. Opt for these 6 workout-friendly brews, here.
Nearly all sports drinks have sodium and carbs, which helps your body hydrate more effectively than water alone. Read the label. You want no more than 500mg of sodium per drink because your body will start pulling water from your blood to help break down the excess minerals. Research published in the journal Medicine & Science in Sports & Exercise also found swishing and spitting out your sports drink during exercise can boost performance by tricking your brain into thinking your body is getting fuel and kick-starting muscle recruitment.
Ok, so sparkling water is just carbonated (or sometimes naturally bubbly) water. But, it's a great alternative to plain tap water because it's calorie-free yet just as hydrating. If you're a soda junkie (see next slide) sipping bubbly water is a great way to wean yourself off of the bad habit.
While the researchers found diet soda and soda didn't affect urine output, other research has found after repeated bouts of dehydration, soda can actually worsen dehydration and increase your risk of kidney damage.
*We'd be remiss not to include this on the list since it was studied, but we're not encouraging you drink the stuff, especially around a workout.