It’s the old wives tale that has divided opinion for decades. Cranberry juice really can help stop urinary tract infections (UTIs), according to the largest review of evidence to date.
A global study looking at the benefits of cranberries found cranberries – in juice or taken as supplements — cut the risk of repeat UTIs in women by more than a quarter.
Children and people susceptible to infections following medical interventions had the odds slashed by 53 per cent, according to the major review.
They were not effective in the elderly, pregnant women, or for people with bladder-emptying problems, researchers found.
A global study looking at the benefits of cranberries found cranberries – in juice or taken as supplements – cut the risk of repeat UTIs in women by more than a quarter. Children and people susceptible to infections following medical interventions had the odds slashed by 53 per cent, according to the major review
Experts believe it is due to their high concentration of the antioxidant proanthocyanidin, which prevents the most common UTI-causing bacteria – Escherichia coli (E.coli) – from sticking to the bladder wall.
Researchers at Flinders University, Australia, looked at 50 more recent trials involving almost 9,000 participants in the latest review, published in Cochrane.
Professor Jonathan Craig, of Flinders University, said: ‘This is a review of the totality of the evidence and as new evidence emerges, new findings might occur.
‘In this case, the new evidence shows a very positive finding that cranberry juice can prevent UTI in susceptible people.’
UTIs are common and can affect the urinary tract, bladder and kidneys, with symptoms including burning when peeing and needing to go more often.
They are often treated with a short course of antibiotics although they are not always needed.
Researchers warned the berries cannot cure an established UTI, so anyone who gets one must seek help from a GP or pharmacist.
Dr Gabrielle Williams, who led the study, said: ‘UTIs are horrible and very common – about a third of women will experience one, as will many elderly people and also people with bladder issues from spinal cord injury or other conditions.
‘Even back in 1973, my mum was told to try cranberry juice to prevent her horrible and frequent UTIs, and for her it’s been a saviour.
‘Despite me niggling in her ear about evidence, she’s continued to take it daily, first as the nasty sour juice and in recent years, the easy to swallow capsules. As soon as she stops, wham the symptoms are back.
‘As usual, it turns out that mum was right! Cranberry products can help some women prevent UTIs.’
Everything you need to know about Urinary Tract Infections (UTIs)
A urinary tract infection, more commonly known as a UTI, is an infection in any part of the urinary system.
UTIs can have different names depending on which part of the urinary tract is infected.
Cystitis affects the bladder, pyelonephritis affects the kidneys and urethritis affects the ureter and urethra.
Signs and symptoms include:
- A burning feeling when urinating
- A frequent urge to urinate, despite little urine coming out upon doing so
- Dark, cloudy or strange-smelling urine
- Fever and chills
- Pain in the lower abdomen or back
Women are much more likely to get a UTI with their risk being as high as 1 in 2 in their lifetime compared to 1 in 10 among men.
The most common cause of UTIs is a transfer of bacteria from the anus to the urethra. Because women have shorter urethras and less distance between the two body parts, it is easier for bacteria to be introduced.
Antibiotics are the most common treatment followed by drinking a lot of water to flush bacteria from the body.
UTIs do not typically lead to death but, when left untreated, they can cause sepsis, a life-threatening condition in which chemicals that the immune system releases into the bloodstream to fight an infection cause inflammation throughout the entire body instead.
The term for sepsis caused by a UTI is urosepsis.
Signs of urosepsis include:
- pain in the lower sides of the back
- nausea and vomiting
- difficulty breathing
- inability to think clearly
- confusion or delirium
A 2019 study found that the risk of a bloodstream infection was more than seven times greater in patients who did not receive antibiotics immediately after seeing a physician for a UTI.
The estimated mortality rate from urosepsis is between 30% and 40%.