Do you put a glass of water next to your bed and refill it every night without washing it off? Or maybe you have a favorite water glass and use that glass for days without bothering to put it in the dishwasher. After all, it’s just water – is it really necessary to wash it?
According to doctors Yes. If you don’t do this, it can even lead to a nasty disease, they say. “The norovirus, a highly contagious virus that causes vomiting and diarrhea, can survive for a week or more in an unwashed glass without adequate cleaning.” Manure Trinhsays MD, founder of the Healthy Brain Clinic Dear life. Read on to find out what else he and other doctors have to say about the hygiene concerns surrounding using the same water glass for a week (and then load up your dishwasher!).
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Drinking plenty of water is good for your body: A recent study linked good hydration habits to living longer and developing fewer chronic health problems. Sure, you have plenty of drink options when you’re thirsty (although you might want to skip the diet soda), but water is the best choice you can make for your health. Going even a day without drinking water can lead to dizziness, fatigue, digestive problems and more.
Still, it is important to take precautions when it comes to the way you drink water. One, doctors say, is making sure you’re not exposing yourself to harmful bacteria and inadvertently increasing your risk of illness by drinking from a dirty glass.
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Whether you use a refillable water bottle or prefer to drink from a regular glass, it’s a widespread practice not to wash the bottle off between fills, doctors note. “Reusing the same glass without washing it is common in many households,” says naturopathic doctor Devin stone, ND, founder of biōReigns. “Sometimes the convenience of just refilling our glass comes before we think about the hygiene issues.”
But some pretty gross things can happen when you get into this habit — and once you get the hang of it, chances are you’ll be scrubbing your water glasses a lot more often.
“If you use the same glass for a week without washing it, bacteria will start to grow on the glass surface,” Peter Michaelsays MD, Chief Medical Officer of VUE Dear life. “It’s important to wash glasses regularly to prevent this buildup with soap and water, not just water alone.”
What if you drink the water and refill it? Will that protect you from bacteria? Trinh says no. “Even if you refill the same glass with fresh water, any bacteria present can quickly multiply and become dangerous,” he explains, citing norovirus as just one of the more unpleasant viruses that can live on an unwashed water glass. And Stone says that over time, bacteria can form a colony called a “biofilm.”
“Without washing and scrubbing these glasses, the bacteria remain in the film, giving them the opportunity to multiply and expand in number,” says Stone. “By doing this, we expose ourselves to unwanted microbes.”
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Even if you wash your water glass regularly, leaving water outside can be problematic, according to all the doctors we spoke to. “A glass left in the open can be exposed to airborne bacteria from dust particles or other sources,” explains Trinh. For that reason alone, it might be the best idea to keep a lidded water bottle on your nightstand. (It also prevents spills, for the accident-prone among us.)
Whichever container you use for your water, don’t forget to top it up with fresh H2O every day. “Bacteria can also grow in the water if it’s not changed often within a few days, so don’t leave the water uncovered next to your nightstand,” warns Stone.