A cider a day keeps the UTIs away

Although cider would not currently be recommended for treatment if you were to seek official medical advice, when you’re 2 hours into a 6-hour train journey late at night, options are limited. The next morning, Claire informed me that her symptoms had cleared, and I immediately sought permission to use this as data in a pilot study.

‘The CIDER for UTI trial: Clinical Ingestion of fermenteD fruit bEveRages for urinary tract infection treatment’… I can work on the name.

Some common symptoms of a UTI are the sudden urge to urinate, increased urination frequency, and a burning or stinging feeling when passing urine. Patients may also feel pain or pressure in the lower abdomen or might notice that their urine is cloudy or contains blood. But these typical symptoms do not always occur straight away. In this case, Claire had a sense of being generally slightly unwell, accompanied by a ‘weird feeling’ in her abdomen, with urinary changes that she put down to drinking too much caffeine. It was only after a few days that the more characteristic symptoms developed.

Patients suffering a potential UTI need rapid access to treatment to relieve symptoms and prevent escalation. Healthcare providers face the challenge of balancing this requirement with the need to avoid unnecessary antibiotic prescriptions when infection has not been identified as the definitive cause. As of 2023, the National Institute for Health and Clinical Excellence (NICE) has updated guidance to recommend that women under the age of 65 who present with two or more key urinary symptoms should be diagnosed with a UTI if other causes have been ruled out. There is no requirement for a confirmatory urine dipstick test to be conducted. This principle is already common practice in some areas and means that women can access treatment and symptom relief more quickly.

Prophylactic treatments and UTI pathogenesis

For the majority, an initial course of antibiotics will clear up the infection within 48 hours. However, recurrent UTIs are common, with around a third of patients experiencing a repeat infection within six months, and nearly half having a repeat infection within a year. Antibiotic prophylaxis before a UTI develops is a widely utilised but potentially controversial option, and many patients resort to alternative therapies, including dietary supplements such as D-mannose.

After this line of thought, I was prompted to expand upon my initial hopes for the therapeutic potential of cider. Could cider be introduced as a prophylactic dietary supplement that would reduce the need for antibiotic prescriptions? Based on the success of a lukewarm can of Strongbow bought on a train, surely even the most resistant bacteria wouldn’t stand a chance against a fruity and aromatic medium-dry vintage cider with a gentle fizz, made from bittersweet organic apples gathered from a single year’s harvest! In other words, could a cider a day keep the UTIs away?

One of the main aims of a good prophylactic treatment would be to prevent the initial bacterial colonisation of the urinary tract. The most common culprit is E. coli, which usually gains access to the urethra via a faecal-perineal route. Upon ascension into the bladder, bacteria must adhere to the epithelial cell walls to avoid being flushed out during urination. However, many uropathogens express adhesin proteins that can bind to high-mannose glycoproteins on the urinary tract cell walls, circumventing the innate defence of the mucosal epithelial layer.

A developing line of UTI therapeutic development aims to target this initial binding process. This is also the principle behind D-mannose supplementation, whereby competitive binding of free D-mannose in the urine to bacterial adhesins prevents adherence to the uroepithelium. Clinical justification for the routine use of D-mannose in UTI prophylaxis is still limited, with no randomised controlled trials having been conducted to test its use. But D-mannose occurs naturally in fruits including apples. And apples are used to make cider. Prime justification for my cider trial right there.

Thorough research using Google failed to enlighten me as to the amount of D-mannose in an apple. I felt that if there was a lack of evidence for using pure D-mannose supplements as a treatment, then arguing for the use of cider on the basis that it is made using a fruit containing a very small amount of D-mannose was probably not going to be a success.

Alternate therapies or urban myths?

My trip down the Google rabbit hole had led me to discover that many people also advocate the use of apple cider vinegar to prevent UTIs. Now this already has the word ‘cider’ in the title so pretty much a guaranteed win. According to the collective wisdom of the internet, apple cider vinegar MAY be the miracle cure for pretty much any medical condition you can think of. And yes, that is ‘may’ in capital letters. The same webpage that told me that apple cider vinegar MAY work as an antimicrobial, also informed me that it MAY reduce belly fat, it MAY balance cholesterol, and that it DEFINITELY tastes good in a salad dressing.

More worryingly, many people seem to advocate the use of apple cider vinegar to help pass a drugs test. Supposedly the trick is to take just 20mL of apple cider vinegar, add 4.5L of water, then down the whole thing as quickly as possible. I’m sure I don’t need to point out here that what this will actually do to you is cause a severe electrolyte imbalance and potentially fatal hyponatraemia.

Going deeper into the apple cider vinegar hype, I discovered that all of its supposed medical benefits are purely based on the fact that vinegar itself has some weak antimicrobial properties, rather than anything to do with the apple and cider components. It appears that specific use of apple cider vinegar as opposed to any other variety might just be because it tastes nicer. There doesn’t seem to be any evidence whatsoever that drinking it will stop a UTI.

At this point I became desperate. Searching for ‘health benefits of cider’ showed me that it contains antioxidants in the form of polyphenols, which can potentially reduce inflammation. Specifically mentioned were proanthocyanidins, the polyphenols responsible for the benefits of everyone’s favourite fruit-related UTI prophylactic, cranberry juice. A recent Cochrane review compared 50 randomised control trials testing cranberry containing products and concluded that cranberry product consumption does reduce the risk of recurrent UTIs in otherwise healthy women. Maybe I could steal this evidence-based principal and rework it for my own cider promoting purposes.

I began to investigate proanthocyanidin concentrations within popular cider brands. Turns out this information is not readily available. Emails to Thatchers and Westons went unanswered, and concerningly I was now being overwhelmed with adverts sponsored by Drinkaware. It appears that there is significant evidence that regular alcohol consumption actually damages your health.

Some actual medical advice

As my hopes of building a convincing case for trial funding dwindled, I decided that lack of evidence wouldn’t be an issue if I could get a genuine medical professional to support me. I approached Dr Eilis Higgins, a registrar at the Countess of Chester Hospital, to explain my idea and hopefully gain her backing. ‘You do realise that drinking alcohol is not recommended for the treatment of any kind of medical condition, is actively advised against in pregnancy, and will likely exacerbate existing conditions and lead to the development of more severe problems if consumed regularly?’ Sounds like a no for support from a medical professional, but I guess I could still try and get a social media influencer on board.

In a last-ditch attempt to gather some evidence to support my trial, I decided to check back in with Claire. Maybe the real-life success story that I had witnessed would be the key. Well, it turned out that the overnight miracle cure wasn’t as miraculous as I had initially thought. Claire had simply been experiencing some temporary symptom relief, and the UTI was back with a vengeance the following day. Had she then tried another cider just in case? No. She spoke to a nurse over the phone and got a three-day course of nitrofurantoin. My dreams of a new UTI treatment were over.

I’ve decided to put my ethics application for ‘The CIDER for UTI trial’ on hold for the time being. I do have my PhD research to be getting on with after all. The three people who eventually read my completed thesis on biocide tolerance in UTIs will undoubtedly find it just as impactful as a full-scale clinical trial would have been. Perhaps it is better just to stick to writing about UTIs. Maybe I could publish an article in an online magazine. I should get on that…

The author would like to emphasise that this article in no way replaces real medical advice, and anyone with concerns about their own health should discuss them with a qualified medical professional. She is also not currently associated with any cider maker or cider producing brand, but if anyone reading this wants to start some kind of cider collaboration she could be interested.