Our regular readers will know that we're always encouraging you to drink more water.
The fact is staying hydrated is great for your body in so many ways - it helps everything from your digestive system to your cardiovascular health.
Staying hydrated can even keep the signs of aging at bay.
But, in the midst of record-breaking summer temperatures, doctors are also sounding the alarm about over-hydrating.
How Much Water Should I Drink Each Day?
Everyone's needs are different, but to keep from getting dehydrated, the National Academies of Sciences have some advice.
They say that healthy men should take in 15.5 cups of water (3.7 liters) each day.
Women, meanwhile, should aim for 11.5 cups (2.7 liters).
Those numbers include water your body gets from food, which accounts for about 20% of your daily intake.
Bear in mind that exercise, your health, and conditions like pregnancy can dramatically change how much water you need.
So does the temperature - and the day doesn't need to be scorching hot to dry you out.
The key, experts say, is to drink when you feel thirsty, which is a sign your body is already dehydrated.
And learn to recognize the signs of heat stroke and heat exhaustion, which include nausea, dizziness, confusion, and headaches.
How Much Water Is Too Much?
Most people assume that since water is so healthy, it's impossible to drink too much. That's not true.
Your body's sodium levels are balanced out by the fluids you take in. Drink too much too fast, and the imbalance can cause hyponatremia, or "water intoxication."
Basically, your body is holding in more fluid than your kidneys can safely flush out, making you sick.
Extra fluid passes through your bloodstream to other parts of the body, where it causes swelling that leads to other symptoms.
Headaches, diarrhea, vomiting, and confusion are all common signs of water intoxication. In dangerous cases, swelling over the brain can even cause seizures or sudden death.
It sounds like a bad joke, but in 2014 a pair of high school athletes died two weeks apart from the same cause: over-hydration.
One high school football player drank "two gallons of water and two gallons of Gatorade" to ward off leg cramps just before he died.
But athletes aren't the only ones vulnerable to water intoxication, so you should be careful.
How To Treat Over-hydration
Heat exhaustion and over-hydration are easy to mistake for each other, because they share symptoms like nausea, muscle cramps, and "brain fog."
Whatever the cause of your symptoms, retreat indoors or to a shady place and call for a doctor immediately.
Avoiding heat stroke is straightforward, and so is protecting yourself from over-hydration.
Drink fluids when you feel thirsty, and stop drinking when you're not thirsty.
If you're exercising or working outdoors, bring fluids to re-hydrate and stop to drink from time to time. It's not always a good idea to "pre-drink" before heading out into the heat.
Switching up water for a sports drink during exercise or on very hot days can be helpful. These drinks contain sodium and electrolytes to balance out your bloodstream.
Overall, try not to worry about over-hydration. While cases of this condition are serious, you're much more likely to be dehydrated.
"These are very isolated cases, and this is extremely rare," explained Dr. Sharon Bergquist of the Emory University School of Medicine."
"More people by far and away are dehydrated, [rather] than having a problem with over-hydration."