Cranberry juice is what your mum, your flatmate or the woman in the pharmacy queue recommends the second cystitis comes up. So does it do anything? A bit, as it turns out. But it depends who's drinking it, and what you're hoping it will do.
Prevention, not rescue
Start with the most useful thing to know. Once a urinary tract infection (UTI) has started, the NHS is clear: there's no evidence cranberry products ease symptoms or treat an infection that's already under way.[2] If you've got that burning, can't-stop-going feeling now, a glass of juice isn't the answer. A GP or pharmacist is.
The question researchers have actually been asking is narrower: can taking cranberry every day make a repeat infection less likely?
What the biggest review found
The best place to look is a Cochrane review, updated in November 2023, which pooled 50 randomised trials and 8,857 people.[1] Across all the groups together, cranberry products were linked to fewer symptomatic, lab-confirmed UTIs, and the reviewers rated that evidence as moderate certainty.
The group with the clearest result was women who get UTIs again and again:
That figure comes from a relative risk of 0.74 in the review.[1] It's a modest effect, not a shield. Plenty of women in those trials still got infections. And the trials varied a lot in design, which the reviewers flagged as a limitation.
Who it helped, and who it didn't
This is the bit most blog posts skip. The same review found a mixed picture depending on who was taking part:[1]
- Women with recurrent UTIs — a reduction in risk (relative risk 0.74).
- Children — a larger reduction in the trials that looked at them (0.46), though the numbers were smaller.
- Pregnant women — no benefit shown (1.06).
- Older adults in care homes — little to no difference (0.93).
So cranberry isn't a universal fix. It looks most useful for a fairly specific group, and even there, a GP should be part of the picture if infections keep coming back. The NHS suggests getting that checked when you've had two UTIs in six months, or three in twelve.[2]
Juice, tablets or capsules?
Honestly, nobody knows which is best. The Cochrane team rated the evidence on juice versus tablets, and on different doses of the active compounds, as very low certainty, and found no clear dose-response pattern.[1] The NHS notes that products come as juice, tablets or capsules taken daily, and flags the sugar in juice, plus a possible interaction with warfarin.[2]
Which is why plenty of people skip the daily glass and choose a capsule. If that's you, look for a clear amount of cranberry extract on the label, and a format you'll genuinely remember to take. Oxford Origins Bio Cultures for Women puts 2,500mg of cranberry extract alongside 3 billion CFU of live cultures in a single capsule a day.
One caveat, and it matters: the research above is on cranberry products in general. We can't tell you that this particular capsule would match the results of those trials, and a supplement isn't a substitute for medical care.
When to put the capsules down and call someone
Get urgent advice if symptoms get worse quickly, or haven't improved within 48 hours of starting treatment.[2] Fever, back or side pain, or blood in your urine are all reasons not to wait it out. And if you're pregnant, have a kidney condition, or take warfarin, talk to your GP or pharmacist before adding anything new.
Cranberry is a sensible, low-drama thing to ask your GP about if recurrent UTIs are wearing you down. Just go in knowing what it can and can't be expected to do. That's the gold standard we'd hold ourselves to, too.
Frequently asked questions
Does cranberry juice cure a UTI?
No. The NHS says there's no evidence cranberry products help ease symptoms or treat a UTI that has already started. If you think you have an infection, speak to a GP or pharmacist.
Can you take cranberry every day?
The NHS describes cranberry products as something taken daily to help prevent repeat infections. Juice contains sugar, and cranberry may interact with warfarin, so check with your GP or pharmacist first if that applies to you.
Is cranberry the same as a probiotic?
No. Cranberry is a fruit extract, while probiotics are live bacteria. The Cochrane review didn't have enough evidence to compare the two. Our guide to which probiotics are best for women goes into the live cultures side in more detail.
Does cranberry work during pregnancy?
In the Cochrane review, trials in pregnant women didn't show a benefit. If you're pregnant and worried about UTIs, talk to your midwife or GP rather than relying on a supplement.
Sources
- Cochrane — Cranberries for preventing urinary tract infections (50 trials, 8,857 participants; subgroup risk ratios; evidence certainty on juice vs tablets and dose). https://www.cochrane.org/CD001321/RENAL_cranberries-prevent-urinary-tract-infections
- NHS — Cystitis (no evidence cranberry treats an existing infection; forms available; sugar and warfarin caution; when to seek urgent help or see a GP). https://www.nhs.uk/conditions/cystitis/
At Oxford Origins, your wellbeing is our priority, and although we pride ourselves on our expertise in nutrition and supplementation, it's important to acknowledge the individuality of each person. Articles published by Oxford Origins are not intended to treat, diagnose, cure or prevent any disease, or replace the advice of your GP. We always recommend consulting with a healthcare provider if you encounter any health concerns, and we'll always be here to support you so you're never alone on your journey.
