Many have heard the rule; drink eight glasses of water a day to be healthy. Most people do not meet the suggest requirement and now, some doctors and nutritionists say the rule is bogus.
David Groener plays baseball overseas.
"I don't think everybody needs eight glasses of water a day," Groener said.
He even spent some time playing in Australia.
"Where I was, the sun was a lot worse and I drank a ton of water, but I still never drank eight glasses of water a day and I was perfectly healthy," said Groener.
New information out of Victoria, Australia suggests the common advice to drink eight glasses of water a day doesn't hold water.
A British doctor also believes the recommendation is "driven by vested interests."
Groener added, "People will do anything they can to make money off of us."
"I think there might be some element of marketing in there as well but I think we just need to be conscientious consumers and be smart about what we're buying. We can drink tap water, that's just as healthy as the bottled water," said Dr. Stephen Pont, with Dell Children's Medical Center.
He says water is still the best option when it comes to drinks.
"The enhanced beverages are unnecessary. Even if you're an athlete, if you're participating in a sport for more than an hour, or it's really hot or humid, you don't even need any of the sports drinks," said Dr. Pont.
There's no denying water's important for your health, but so is a balanced diet. That means regularly eating fruits and vegetables.
Most fruits are at least 80 percent water. Some are closer to 100 percent. Even a starchy vegetable like a potato, is 75 percent water.
"You get that water, it fills you up. You have more vitamins, you have fiber in there too, but if you shift to the more processed foods, a lot of those things are taken out," said Dr. Pont.
There's an easy way to gauge your hydration level.
"If their urine is very dark and yellow, we know they probably need some more water, or, not probably, they really need some more water. If its lighter yellow or white, then we know they're well hydrated," said Dr. Pont.
"I just stick with water and as long as I have as much going in as I have coming out, it all works out," said Steve Uhler.
He works out every day and says his best partner is H2O.
"It's been around so long, I'm afraid I kind of live by it," Uhler said. "I had about six glasses of water before I even stepped out the door here, so I'm hydrated."
John Schieffer and his dog Maggie also live by the eight glasses a day rule.
"I'll still keep drinking water. It's still two parts hydrogen and one part oxygen," said Schieffer.
"You got to listen to your body and don't always believe what you hear," said Groener.
Not everyone's buying it. Plus, no one really knows where the rule came from in the first place.
Doctors say kids become dehydrated faster than adults.
In some rare cases, people have died from consuming too much water, too quickly.