Too much of a good thing? Water overdose is real, and it’s scary

Symptoms of overhydration much like dehydration

Glass of water. (Photo by Stephan Müller from Pexels.)

While most of us need to be reminded to drink more water, there is always an exception to the rule.

Ever heard of hyponatremia? It’s a fancy word for water intoxication, and it happens when you drink too much water.

It seems people everywhere are constantly reminding us: “You need to drink more water.” So how in the world does overhydration even happen?

Balance in the body

Well, it all comes down to sodium levels. The sodium in our body has the job of balancing fluids in and around the cells, according to the National Institutes of Health. Drinking too much water can cause an imbalance, forcing the liquid to move from your blood to inside your cells, making them swell. Swelling in the brain can be serious and sometimes fatal. It can also trigger seizures and coma.

In addition, your kidneys filter everything you drink and make sure the fluid levels in your bloodstream stay balanced. When you drink too much water, it makes your kidneys work overtime, leaving your body stressed and fatigued.

How much is too much?

So how much water is too much? To be clear, it would take a lot (times a lot) for someone to suffer from water intoxication. We’re talking about an intake of gallons of water. The fatal cases are isolated, and extremely rare.

What about someone who's especially active, like, say, training for a marathon? Or a woman who is pregnant or nursing a child? Take heart in knowing that people in different circumstances do require a higher intake of water.

In reality, the majority of people tend to have a problem with dehydration rather than overhydration.

“Young, healthy people don’t normally (get hyponatremia) unless they drink liters and liters of water at once, because your kidneys can only (expel) about half a liter, at most, an hour,” said Chris McStay, an emergency medicine doctor. “You’re drinking more than your kidneys can pee out.”

Similarities to dehydration

The ironic thing about being overhydrated is that a lot of the symptoms are much the same as being dehydrated.

“It’s often hard to tell the difference … between water intoxication and heat exhaustion, unless you know they drank 6 gallons of water," McStay said.

So what are some signs you may be drinking too much water?

What’s the right amount?

Having said all this, it begs the question: How much water should one be drinking in a day?

Unfortunately, there isn’t an exact recommended daily allowance for water consumption.

Ultimately, the consensus among experts is to drink until you don’t feel thirsty, then stop.

McStay said a good way to tell if you need to drink more water is to take a look at your urine. If it’s dark, you’re probably dehydrated, and you should drink.

For those who are more active, sometimes it helps to have sports drinks, which contain more electrolytes. However, it’s worth noting that you want to pay attention to the amount of sugar in the drinks, which experts recommend should be about 5 grams per 8-ounce serving.

But if you really want a hard number to start with, experts at the Mayo Clinic say a goal of eight glasses a day is reasonable for a sedentary person. However, you will likely need to modify your intake if you’re exercising, sick, pregnant or breastfeeding, or live in a hot or humid area or at a high altitude.