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Why Your Water Tastes Funny After Being Left Out Overnight

A woman picks up a glass of water from a nightstand.
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If you’re like me, you’re thirsty first thing in the morning. You might even leave a glass of water on your nightstand for a first-thing-in-the-morning sip. But have you ever noticed it tastes funny?

Well, you’re not imagining things. Your water does taste funny first thing in the morning, and it’s all about how exposure to air alters it.

Well + Good spoke with Kelly Johnson-Arbor, MD, medical director of the National Capital Poison Center, who explained what that funky taste occurs. Johnson-Arbor said carbon dioxide dissolves within the water, and it’s converted in our bodies to carbonic acid. The longer you let your water sit out, the more acidic compounds develop, making it taste odd. The acidic elements give the water a stale and bitter taste.

Ello Cooper Vacuum Insulated Stainless Steel Water Bottle

Stash your water in a sealed bottle to ensure freshness.

Now, hearing that carbon dioxide is why your water tastes weird might freak you out, but it shouldn’t. According to Johnson-Arbor, the unpleasant is just that, unpleasant, not dangerous. The bigger issue is whether bacterial production has occurred if water is allowed to stand overnight.

If you are thirsty first thing in the morning, you might want to stash a water bottle in the fridge, and hey, at least it’ll force you to get up, right?

Shea Simmons Shea Simmons
Shea Simmons is the Assignments Editor at LifeSavvy. Previously, she worked as a freelance writer with a focus on beauty and lifestyle content. Her work has appeared in Bustle, Allure, and Hello Giggles. Read Full Bio »
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