Reusable water bottles tick many boxes. Not only do they help you stay hydrated and help save money, but they also help cut down on single-use plastic. They've almost become a fashion accessory, with chic stainless steel flasks and viral bottles going viral across TikTok. Sign up for our free Indy100 weekly newsletter Trying to hit the NHS-recommended eight glasses of water a day for adults is an excellent idea, of course, but did you know there’s one way your refillable bottle could potentially be detrimental to your health? According to a study from waterfilterguru.com, reusable water bottles contain an average of 20.8m colony-forming units (CFUs) of bacteria, which equates to 40,000 times more than the microbes on a toilet seat. So what might be the consequences if you continuously sip and refill without washing your bottle properly between uses? We asked health experts to talk through the risks… Bottling up bacteria “A common misconception when it comes to reusable water bottle hygiene is that as you’re typically filling it with pure water and it’s only coming into contact with your own mouth, there’s little need to clean it often,” says Dr Donald Grant, senior clinician at The Independent Pharmacy. However, every time you drink from the bottle, you’re transferring bacteria from your mouth, which can then multiply in the container. “Anything that is reusable can be prone to accumulating dirt, dust or debris and, as a result, bacteria,” says private GP Dr Suhail Hussain. “This is exacerbated by the fact water bottles are the ideal environment for harbouring bacteria due to being moist.” Hard-to-reach crevices – for example, inside a screw top or under a flip-up straw – could also develop mould, and then there’s contamination from other sources. “When you store it in a gym bag, for instance, it can pick up bacteria from the interior of the bag or anything else stored in it, while you can also transfer bacteria from your hands to your bottle,” says Grant. “If your bottle has a valve cap, you may need to lift or twist it with your fingers, and this can transfer bacteria you may have picked up from touching other objects or surfaces.” What types of microbes are found in water bottles? “These might be simple commensals such as streptococcus and staphylococcus, which normally live in symbiosis with their host (i.e. us) but can become problematic if they accumulate or the individual is under the weather,” Hussain says. “Bacteria such as E. coli – a common cause of urine and bowel infections – can often colonise the water bottle following repeated handling, such as taking the cap on and off.” These bacteria can potentially cause a variety of issues. “You may become sick and develop gastric illness, such as diarrhoea or vomiting,” Hussain continues. “Gram negative rods – another common bacterium found in unwashed bottles – can lead to urogenital tract infections and pneumonia.” Grant warns: “If there’s a build-up of mould inside the bottle, this can cause allergy symptoms, such as a runny nose, sneezing, or red and itchy eyes. Symptoms might be more severe for someone with asthma.” How often should you wash your reusable water bottle? “To minimise your risk of getting sick, you should ideally clean your water bottle after each use,” Grant says. “As a minimum, you should aim to wash it thoroughly at least a few times a week.” Hot water and washing up liquid are all you need to banish bacteria on a daily. “Fill the bottle with hot soapy mixture and swill around, or leave to soak in a detergent mixture,” Hussain advises. “Remember to pay special attention to lids/caps and screw top regions – use a clean brush [to scrub them].” If you’ve neglected your bottle for a few days and it needs a deeper clean, Grant suggests: “Soak your bottle overnight in a solution of half vinegar and half water. Rinse the bottle and let it dry fully before using it again.” Storage is also important to help minimise nasty microbes. “Where possible, you should keep your water bottle out of germ-rich environments such as your gym locker or sports bag,” Grant says. “You should also avoid filling your bottle with anything other than water, such as protein shakes, energy drinks, or sugar-rich liquids, as sugar can stimulate the growth of bacteria.” Hussain adds: “Don’t leave a water bottle in the sun for long periods or sitting in the cup holder in the car – the mixture of warmth and moisture is likely to make bacterial overgrowth worse.” Have your say in our news democracy. Click the upvote icon at the top of the page to help raise this article through the indy100 rankings.

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The heavyweight division is a bad pantomime now with Tyson Fury, Oleksandr Usyk, a chorus of fighters, a few promoters and some hefty backers all trying to work out what part of the dancing horse they are. Moving away from the ugly sisters, there is every chance that the gap between the last championship fight and the next will be the longest in over 50 years. This break is not common, ignore people telling you that. Fury defended his WBC title last December against his old, old friend, Dereck Chisora, and Usyk beat Anthony Joshua for the second time last August in Saudi Arabia to retain his IBF, WBA and WBO titles. Fury has no date, just social media plans, and Usyk is due to defend in Poland in late August against Daniel Dubois. It is hard to find a solitary reason for the break and even more difficult to put the blame on just one single person. There are a lot of people on the stage, and they all have a role to play. And to be honest, during the last six months they have all said too much. Sure, greed, rivalries, stupidity, lies and ego are at the very core of the problem, but boxing at the highest level has always had the same flaws, the same fluid obstacles. The standard excuses are there to overcome - that is how boxing works. Fury and Usyk for all the tarnished marbles was meant to have been signed and sealed last September. It was scheduled for April and is now a plan for December. Both boxers have insulted the other, and the theme of their mutual abuse is simple: greed. Obviously, both deny they are the greedy, money-grabbing party in the sad affair. Actually, the righteous outrage from both sides is comedy gold at times. Fury’s father, the unstoppable “Gypsy John” Fury, has demanded that Usyk apologise for his criticism. He has warned that if there is no apology, there might be a straightener in a field somewhere, man-to-man. There is honour at stake. It is endless mirth, it really is. c. Some of boxing’s wisest, richest and smartest brains have been involved in this ongoing lunacy. The men and women in the Fury camp blame Usyk, and the men and women in the Usyk camp blame Fury. The two main players in the Fury business, Bob Arum and Frank Warren, have a combined total of 98 years of promotion; they are both battling this madness. There is, according to some insiders, a one-off offer on the table from the government of Saudi Arabia for Fury and Usyk to fight there at the end of the year. Usyk has signed his deal. This offer is non-negotiable, and we know this because the media flown out to Saudi by the Saudi government have reported it as fact. As a guide to the way boxing works, there are seldom any facts involved when deals are being made, broken and made again. The real insiders are furious that Usyk and Fury, the biggest fight in boxing, is not yet across the line. The sanctioning bodies, who get paid a fee for fights, have promised to get tough with their heavyweight champions, but have not said a word or done a thing; everyone is holding out for a slice of the Saudi cash pie. ‘Hey, it’s a business,’ they will say, but that little claim is wearing very thin. Fury, meanwhile, has mentioned 10 possible opponents in his social media rants in the last few weeks, including a plan to fight two UFC icons in one night. Usyk and Dubois went to purse bids, which is one of boxing’s ancient rituals, and Usyk’s team won. The fight is scheduled for August. Looking in from the side of the crowded stage is Joshua. His fight with Fury was announced by Fury on 10 June, 2020; it would have been a fight for the ages, for all the belts and all the bragging rights. It never happened and it has come close a couple of times since then. Joshua, meanwhile, will fight in August and it might be Dillian Whyte. There is a rumour that Whyte wants too much for the fight; the flip side of that rumour is that Whyte was offered too little. In America, Deontay Wilder, twice beaten in classics by Fury, has not fought since last October. There is a plan, under the Saudi deal, for Wilder to fight Joshua in Saudi Arabia on the same night as Usyk and Fury fight. There is, so the paid publicists insist, a total purse of $400million on the table for the four boxers to split. It must be a strong table. There are bold plans right now for the deadlock to be broken soon and some concrete dates and fights to finally be announced. The traffic, as they say in the world of espionage, is heavy. Let’s hope for some fights – the old game needs the best heavyweights back in action and out of the back end of that horse suit. Click here to subscribe to The Independent’s Sport YouTube channel for all the latest sports videos. 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