How often should you wash your water bottle?

How often should you wash your water bottle?

Do you use your reusable water bottle multiple days in a row without washing it? Do you wash it and then refill it before it dries completely?

Both habits can lead to bacterial growth and illness.

A study published in Food Protection Trends looked at the germs in 90 reusable bottles and found that coliform bacteria like E. coli, which can cause stomach illness, was among the most common.

The 2017 study showed that saliva backwash in your water bottle leads to bacteria breeding, especially if you keep your water bottle at room temperature all day or use an opaque bottle, as dark and moist environments are breeding grounds for bacterial growth. The study pointed out that while consumers may realize the importance of cleaning food-contact surfaces, they don’t realize that it’s just as important to thoroughly clean water bottles. Besides E.Coli, other common food-borne organisms associated with unclean water consumption include Salmonella and Campylobacter.

“At a minimum, you should pour out water from your reusable water bottles at the end of each day to eliminate some germs,” says Dr. Robert Citronberg, an infectious disease specialist at Advocate Lutheran General Hospital in Park Ridge, Ill.

“However, to get rid of the bulk of the bacteria and decrease your likelihood of getting a stomach bug, you should scrub the entire bottle, inside and outside, including the lid and straw, and let it air dry completely after you finish each time,” says Dr. Citronberg. “The use of a bottle brush for these popular tall bottles that have the thin necks is key, and I recommend using dish soap, or better yet, a bleach-based cleaning product labeled safe for drinkware.”

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  1. I wash them out first with Dawn Ultra and a bottle brush, then fill the bottle up with water and 2 tblsp. of laundry bleach, let sit 5 min, then fill with clean cold water, let it sit another 5 min, repeat, then let the bottle air dry overnight. I also hit the spout, inside and out, with a toothbrush and bleach before rinsing. Seems to do the trick though I only do this once per week-I alternate with several bottles. Always flush the bottle with clean water before refilling.

  2. Also a good idea to remove the rubber seal found on many water bottles and clean both the seal and the area that it sits in thoroughly.

  3. Honestly if I did this every single day, I would give up drinking water. It’s too much work. There is a reason that people (not me) buy plastic water bottles. Drink and toss is so much easier. I will at least start emptying my water bottle everyday and washing it once a week. That’s about as good as it’s going to get for me. 🙂

  4. Linda, I agree with you. I’ve been leaving my cup empty at the end of the day and washing it once a week. Seems to work for me.

  5. I thought washing my bottle twice a week was enough to keep the bacteria away! Yet upon reading this, I realized how unsanitary it was. Cleaning it every day may be tiring, but it’s the safest way possible.

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About the Author

Kate Eller
Kate Eller

Kate Eller was a regional director of public affairs and marketing operations for Advocate Health Care. She enjoys road trips, dogs, minimalism, yoga, hiking, and “urban hiking.”