How often should you clean your water bottle?
MINNEAPOLIS — Like a security blanket for adults, it seems like everyone has a reusable water bottle within arm's reach.
You'd think bottles were a school supply given how many students at the University of Minnesota have them.
"I carry it every day," said student Ariana Payton.
"When I go to lunch or dinner, I bring this. Go to class or gym, it's my go-to water bottle," said student Daniel Budiman.
Some are plastic or steel; some come with a straw; others a nozzle. They can be known for functionality or colorful style. No matter the look, all eventually need a good rinse.
"I would say (I clean my bottle) probably every other week. Maybe once a week," Budiman said.
"Right now, I clean it every three days," Payton said.
A survey by WaterFilterGuru.com found that 62% of people clean their water bottles at least once a day; 25% clean them a few times a week; and 13% clean them just a few times a month.
Amy Johnston, a University of Minnesota Extension educator who specializes in food safety, says you should wash your bottle daily, whether by dishwasher or by hand with warm water and soap.
"That's just going to prevent any buildup of bacteria," Johnston said.
She says bacteria can multiply in number quickly, doubling their amount almost every 20 minutes.
Touching the lid with dirty hands and rising temperatures can accelerate bacteria's growth. So too can the type of liquid left behind.
"A sugary drink, or any kind of flavoring component, those sugar and flavor components can be food for bacteria if there are bacteria present," she said.
Bacteria seem to love water bottles more than other dirty places. WaterFilterGuru.com had scientists swab common household surfaces for comparison. The study found reusable water bottles had:
- Five times more bacteria on them than a computer mouse
- 14 times more bacteria than a dog bowl
- 40,000 times more bacteria than found on a toilet seat
Which part of the bottle is most conducive to bacteria growth?
"All those little nooks and crannies are where bacteria are going to want to hide," Johnston said.
Straws, nozzles and sipping points need the most attention when cleaning, so much that Johnston advises people to do so by hand to ensure nothing's missed in a dishwasher.
People should also let water bottles air dry completely after cleaning. That will help prevent mold growth.
In addition to cleaning, Johnston said sanitizing should be considered. There are several ways to do that. One method is to submerge the bottle and components in extremely hot water, at least 160 degrees, for about 30 seconds. You can add vinegar or baking soda to the water as well.
Johnston says sanitizing is more important if you use other drinks besides water in the bottle.
