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Does cranberry juice help with UTIs? What the trials show

Cranberry juice and capsules cut repeat UTIs by about a quarter to a third in women, and by about half in children, pooled trials found.

Published October 2026

Short answer

Cranberry products lower the chance of repeat urinary tract infections: about a quarter to a third fewer in women with recurrent UTIs, and about half as many in children. There is no good evidence they clear an infection you already have. Evidence grade B (Moderate). A Cochrane review of 50 randomised trials (8,857 participants) and later meta-analyses agree on a modest reduction in recurrent UTIs; downgraded once for high heterogeneity (I2 = 69%) and because several subgroups show no benefit.

Key takeaways

  • Across 26 trials with 6,211 people, cranberry products cut symptomatic, culture-confirmed UTIs by about 30% [1].
  • In women with recurrent UTIs, 8 trials with 1,555 women found about a quarter fewer repeat infections [1], and a 23-trial meta-analysis found similar results [2].
  • Children had about half as many infections (5 trials, 504 children), and so did people whose risk rose after a medical procedure (6 trials, 1,434 people) [1].
  • In a 24-week trial, 373 women who drank 240 mL of cranberry juice daily had 39 UTI episodes versus 67 with a placebo drink, about one infection prevented per 3.2 woman-years [3].
  • Cranberry capsules did not help older women in nursing homes (29.1% versus 29.0% for bacteria plus white cells in urine) [4], and no eligible trial has tested cranberry for treating an infection that has already started [5].

The short version

Cranberry products - juice, capsules or tablets - can help stop urinary tract infections (UTIs) from coming back. Pooled trials found about a quarter to a third fewer repeat infections in women, about half as many in children, and fewer infections in people at higher risk after some procedures [1][2]. The evidence covers prevention: a Cochrane search for trials of cranberry as a treatment found none that met its standards [5].

What the studies show

The biggest body of evidence is a 2023 Cochrane review that pooled 50 randomised trials with 8,857 participants [1]. Across 26 of those trials (6,211 people) that counted symptomatic, culture-confirmed UTIs, cranberry products lowered the risk by about 30% (risk ratio 0.70) [1]. The benefit held in women with recurrent UTIs (26% lower risk, 8 trials, 1,555 women), in children (54% lower, 5 trials, 504 children) and in people whose UTI risk rose after a medical procedure (53% lower, 6 trials, 1,434 people) [1]. A 2021 meta-analysis of 23 trials (3,979 people) found almost the same numbers, including about half as many infections in people using catheters [2]. A 2025 network meta-analysis of 50 trials (10,495 people) found cranberry lowered UTI risk by 28% compared with placebo [6].

Individual trials in women with recurrent UTIs point the same way. In a 24-week trial, 373 women drank 240 mL of a cranberry beverage or a look-alike placebo; the cranberry group had 39 UTI episodes versus 67, and roughly one infection was prevented for every 3.2 woman-years of use [3]. A 2024 trial found 240 mg of cranberry proanthocyanidins a day roughly halved UTI episodes over 12 months in 160 women [7]. A 2025 trial found a 500 mg whole-fruit cranberry powder cut culture-confirmed UTIs by about half over six months in 150 women [8].

Not every group benefited. In older women living in nursing homes, cranberry capsules did not change how many had bacteria plus white cells in their urine (29.1% versus 29.0%) or how many had symptomatic UTIs (10 versus 12 episodes) [4]. The Cochrane review found no clear benefit in care-home residents, pregnant women, or people whose bladders do not empty fully [1].

The nuances

The trials used different products: 240 mL of cranberry juice or juice drink a day [3], capsules with 240 mg of proanthocyanidins [7], 72 mg from two capsules [4], or 500 mg of whole-fruit powder [8][9]. Cochrane could not tell whether juice and tablets differ, and found no clear sign that higher proanthocyanidin doses work better [1]; a 2024 review suggested at least 36 mg a day, taken for 12-24 weeks, may be the range linked to fewer infections [10]. A 2024 network meta-analysis of 20 trials (3,091 people) estimated cranberry juice lowered UTI rates by 54% compared with no treatment and 27% compared with a placebo drink, and cut antibiotic use by 49-59% [11].

Two things to keep in mind. First, funding: the 2025 powder trial was paid for by a supplement company [8], and a 2017 meta-analysis was partly funded by a cranberry company [12]. Second, safety: stomach upset was about as common with cranberry as with placebo in the trials [1]. Case reports have linked cranberry to stronger warfarin effects, but a randomised trial in 30 people taking stable warfarin found no effect on warfarin levels in the blood [13], and a safety review found the reported interactions involved very large intakes (1-2 litres of juice a day or high-dose extracts), mostly in people who were already seriously ill [14]. A 2021 systematic review still lists cranberry among foods reported to interact with warfarin, so a doctor is worth asking if that applies to you [15].

For an infection you already have, the picture is different. A Cochrane review searched for randomised trials of cranberry as a treatment and found none that met its standards, so there is no good evidence that cranberry clears an infection once it has started [5]. A small 2021 study showed a proper trial in UK general practices could be done, but it was not designed to show whether symptoms improved [16].

What this means for you

For women who get UTIs again and again, the trials suggest cranberry products cut repeat infections by about a quarter to a third - about one infection avoided per 3.2 woman-years of daily juice in the largest trial [3][1]. Fewer repeat infections can also mean fewer antibiotic courses: a 2024 network meta-analysis found cranberry juice lowered antibiotic use by 49-59% [11]. Cranberry is not a stand-in for treating an infection that has already caused symptoms; the trials tested prevention, and the treatment evidence is missing [5]. If you take warfarin or another blood thinner, talk to your doctor before adding cranberry products [15].

Go deeper

  • Cranberry — Cranberry products - juice, capsules or tablets - help prevent repeat urinary tract infections: pooled trials found about a quarter to a third fewer infections…

References

  1. Cranberries for preventing urinary tract infections.. Cochrane Database Syst Rev, 2023.
  2. Consumption of cranberry as adjuvant therapy for urinary tract infections in susceptible populations: A systematic review and meta-analysis with trial sequential analysis.. PLoS One, 2021.
  3. Consumption of a cranberry juice beverage lowered the number of clinical urinary tract infection episodes in women with a recent history of urinary tract infection.. Am J Clin Nutr, 2016.
  4. Effect of Cranberry Capsules on Bacteriuria Plus Pyuria Among Older Women in Nursing Homes: A Randomized Clinical Trial.. JAMA, 2016.
  5. Cranberries for treating urinary tract infections.. Cochrane Database Syst Rev, 2023.
  6. Nonantibiotic prophylaxis for urinary tract infections: a network meta-analysis of randomized controlled trials.. Infection, 2025.
  7. Randomized, placebo-controlled, double-blinded study of prophylactic cranberries use in women with recurrent uncomplicated cystitis.. World J Urol, 2024.
  8. Whole cranberry fruit powder supplement reduces the incidence of culture-confirmed urinary tract infections in females with a history of recurrent urinary tract infection: A 6-month multicenter, randomized, double-blind, placebo-controlled trial.. Am J Clin Nutr, 2025.
  9. Are High Proanthocyanidins Key to Cranberry Efficacy in the Prevention of Recurrent Urinary Tract Infection?. Phytother Res, 2015.
  10. Preventive effect of cranberries with high dose of proanthocyanidins on urinary tract infections: a meta-analysis and systematic review.. Front Nutr, 2024.
  11. Cranberry Juice, Cranberry Tablets, or Liquid Therapies for Urinary Tract Infection: A Systematic Review and Network Meta-analysis.. Eur Urol Focus, 2024.
  12. Cranberry Reduces the Risk of Urinary Tract Infection Recurrence in Otherwise Healthy Women: A Systematic Review and Meta-Analysis.. J Nutr, 2017.
  13. The absence of an interaction between warfarin and cranberry juice: a randomized, double-blind trial.. J Clin Pharmacol, 2009.
  14. Safety of Cranberry: Evaluation of Evidence of Kidney Stone Formation and Botanical Drug-Interactions.. Planta Med, 2021.
  15. Warfarin and food, herbal or dietary supplement interactions: A systematic review.. Br J Clin Pharmacol, 2021.
  16. Does cranberry extract reduce antibiotic use for symptoms of acute uncomplicated urinary tract infections (CUTI)? A feasibility randomised trial.. BMJ Open, 2021.