It's not likely you'll get sick from drinking old water that's been out overnight.
Image Credit: LIVESTRONG.com/Creative How Bad Is It Really? sets the record straight on all the habits and behaviors you’ve heard might be unhealthy. Leaving a glass of water on your nightstand is a relatively common practice. If you wake up thirsty in the middle of the night or morning, you’ll be thankful for the readily available H2O.
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Expiration dates aren't required on bottled water, so it doesn't necessarily go bad, per the Minnesota Department of Health. But whether or not you should drink stale water that's been sitting out on your nightstand or counter all night — or for hours in a hot car — is up for debate.
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To find out what can happen if you leave a glass of water out overnight and drink it, we chatted with Kelly Johnson-Arbor, MD, a medical toxicology physician and co-medical director at National Capital Poison Center. Here's what she had to say.
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1. It Might Become Contaminated
Without a lid, contaminants can get into your glass of water. “An open glass is susceptible to contamination by dust, germs, insects,” Johnson-Arbor says. “This also includes anything else floating or flying in the air.” Your body digests bugs or “anthropods” just like any other food, so this may not actually harm your health as much as it may gross you out, according to the Mayo Clinic.
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That said, research shows toxic chemicals can be found in household dust, and over time, taking in high amounts is associated with health problems, per UC Davis.
It Might Taste Bitter If you’ve ever chugged a glass of water that was left out overnight, you may have noticed the subtle difference in taste. There’s an explanation for this, Johnson-Arbor says.
Advertisement “When you leave a glass of water out overnight, gasses in the air, including carbon dioxide, dissolve in the water,” she says. “When carbon dioxide dissolves in water, it is converted to carbonic acid, which is why leftover water might taste bitter.”
It Can Contain Bacteria Your mouth is home to about 700 species of microbes, according to the National Institutes of Health (NIH). That’s a lot of bacteria.
Advertisement Drinking from a glass will result in backwash — when liquids mix with the bacteria in your mouth before returning to the container. This is why Johnson-Arbor says you should avoid drinking from a glass of water that was left out overnight if someone else used it before.
Advertisement “Our mouths contain numerous species of bacteria that can contaminate water bottles or glasses that we drink out of,” she says. “While our own bacteria are unlikely to cause harmful effects if we reuse a water bottle or drinking glass after leaving it out overnight, these germs could be harmful to other people and vice versa.”
Advertisement So, How Bad Is It Really to Drink Water That’s Been Out Overnight? Drinking water that’s been out overnight mainly alters the taste but not the safety of the water. Things you might find gross could get in your glass, such as bugs and dust, but these are likely harmless. “Overall, even though water might not taste as good if it’s been left out overnight, it’s unlikely to make someone sick,” Johnson-Arbor says. “It’s generally safe to drink water that has been left out overnight as long as there is no visible contamination of the water.”
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references
Minnesota Department of Health: "Bottled Water: Questions and Answers" U.S. Environmental Protection Agency: "Particulate Matter (PM) Basics" Acta Biomed: "The effect of temperature and storage time on the migration of antimony from polyethylene terephthalate (PET) into commercial bottled water in Kuwait" National Institutes of Health: "Mouth Microbes" Mayo Clinic: Should You Worry if You Accidentally Swallow a Bugreferences
Minnesota Department of Health: "Bottled Water: Questions and Answers" U.S. Environmental Protection Agency: "Particulate Matter (PM) Basics" Acta Biomed: "The effect of temperature and storage time on the migration of antimony from polyethylene terephthalate (PET) into commercial bottled water in Kuwait" National Institutes of Health: "Mouth Microbes" Mayo Clinic: Should You Worry if You Accidentally Swallow a BugIt’s not likely you’ll get sick from drinking old water that’s been out overnight. Image Credit: LIVESTRONG.com/Creative
How Bad Is It Really? sets the record straight on all the habits and behaviors you’ve heard might be unhealthy.
Image Credit: LIVESTRONG.com/Creative
How Bad Is It Really? sets the record straight on all the habits and behaviors you’ve heard might be unhealthy.
How Bad Is It Really to Reuse a Plastic Water Bottle?
by
Molly Triffin
How Bad Is It Really to Never Clean Your Water Bottle?
by
Isadora Baum
How Bad Is It Really to Microwave Plastic?
by
Kayla Hui
How Bad Is It Really to Skip Breakfast?
by
Lindsay Tigar
How Bad Is It Really to Take Melatonin Every Night?
by
Marygrace Taylor
Minnesota Department of Health: "Bottled Water: Questions and Answers"
U.S. Environmental Protection Agency: "Particulate Matter (PM) Basics"
Acta Biomed: "The effect of temperature and storage time on the migration of antimony from polyethylene terephthalate (PET) into commercial bottled water in Kuwait"
National Institutes of Health: "Mouth Microbes"
Mayo Clinic: Should You Worry if You Accidentally Swallow a Bug
