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Can your drink bottle make you sick?

Your reusable water bottle could be swarming with bacteria!

A young woman with headphones around her neck takes a sip of water as she walks across a bridge
A young woman with headphones around her neck takes a sip of water as she walks across a bridge

We all know the benefits of keeping hydrated, but did you know that your water bottle could be making you sick?

And, if you’re using a reusable drink bottle you could be in some hot water.

EmLab P&K laboratory tested 12 bottles for bacteria after they’ve been used for a week by an athlete. Their thirst for knowledge uncovered some pretty grimy results.

The dirty truth

As part of the study, the researchers tested four different types of common reusable bottles – slide tops, squeeze tops, screw tops and straw tops – and some of the bottles housed more than 900,000 units per square centimetre (CFU/sq cm) of viable bacteria cells.

To give you some perspective, the average toilet seat has a measly 27 CFU/sq cm.

An infographic of the level of germs on different types of water bottle lids

But, is bacteria really that bad for you?

If you haven’t jumped aboard the probiotic train yet, it’s time to be schooled. Probiotics, which are found in yoghurt, kombucha and fermented foods, are live bacteria, but not the ‘germy’ type that can make you sick. Instead, this type of bacteria may help prevent illness, promote a healthy digestive tract and boost your immune system – it’s even been suggested to have a positive impact on your mood!

So the study categorised the different types of bacteria found on each water bottle. If your h2o flask is crawling with beneficial bacteria, you’re going to want as many of those organisms as possible.

So which bottle is best?

Believe it or not, the straw top bottle is by far the best option for your next workout – not only does it have the least amount of bacteria, but only 8% of the germs present are the kind that could make you sick. The reason the straw top bottle reigns supreme could be because any leftover water drips to the bottom of the straw, as opposed to resting on the mouthpiece and attracting more and more moisture-loving germs.

If you’re looking to buy a new water bottle, aim to pick one that has the least amount of crevices possible – the fewer places that bacteria can hide, the better.

Don’t let it dampen your spirits if your favourite bottle isn’t of the straw-top variety. Minimising the nasty bacteria comes down to cleaning it correctly.

An infographic displaying the number of germs on a slide-top, squeeze-top, screw-top and straw-top water bottle

How do I clean my reusable water bottle?

The easiest way to clean your water bottle is by running it through your dishwasher – but make sure you put it on the drying cycle to get rid of any moisture (moist environments are breeding grounds for bacteria).

If your bottle has a squeeze top, removable straws or complex crevices, it might be better to scrub it with a brush and then let it air dry overnight.

Keen to keep healthy at the gym? Check out our article on the four types of activewear that could work against you during your workout.