Do you carry a refillable water bottle with you every day? Did you know that your seemingly innocuous bottle could be harboring more bacteria than the average toilet seat? Yes, you read that right. In fact, reusable water bottles contain an average of 20.8 million colony-forming units (CFUs) of bacteria, which is equivalent to 40,000 times more than the microbes on a toilet seat!
So what could happen if you keep refilling and drinking from your bottle without cleaning it between uses? Brace yourself for the answer, folks. Every time you drink from the bottle, you're transferring bacteria from your mouth, which can then multiply in the container. Hard-to-reach crevices - like inside a screw top or under a flip-up straw - could also develop dreadful mold. According to Dr. Suhail Hussain, a private GP, "Anything that is reusable can be prone to accumulating dirt, dust or debris and, as a result, bacteria. This is exacerbated by the fact that water bottles are the ideal environment for harboring bacteria due to being moist." But wait, it gets worse. When you store your bottle in a gym bag or any other bag, it can pick up bacteria from the interior of the bag, or anything else stored in it. You can also transfer bacteria from your hands to your bottle. Yikes!
Bacteria such as E. coli - a common cause of urine and bowel infections - can colonize the water bottle following repeated handling. As a result, you may become sick and develop gastric illness, such as diarrhea or vomiting. Moreover, Gram-negative rods - another common bacterium found in unwashed bottles - can lead to urogenital tract infections and pneumonia. "To minimize your risk of getting sick, you should ideally clean your water bottle after each use," warns Dr. Donald Grant, senior clinician at The Independent Pharmacy. "As a minimum, you should aim to wash it thoroughly at least a few times a week." So, to get rid of the bacteria breeding ground, all you need is hot water and washing up liquid. To clean hard-to-reach areas, use a clean brush to scrub. If you've neglected your bottle for a few days, soak it overnight in a solution of half vinegar and half water. Rinse the bottle and let it dry fully before using it again.
Finally, storage is also important to help minimize nasty microbes. Keep your water bottle out of germ-rich environments such as your gym locker or sports bag, and avoid filling it with anything other than water, as sugar can stimulate the growth of bacteria. Don't leave a water bottle in the sun for long periods of time or sitting in the cup holder in the car - the mixture of warmth and moisture is likely to make bacterial overgrowth worse.