Study Reveals Why Cranberry Juice Benefits May Vary From Woman to Woman - Video

Cranberry juice may help prevent urinary tract infections (UTIs) in some women, but its effects appear to vary between individuals, according to a study published in Nutrients.

Researchers examined whether differences in metabolism could explain why previous clinical trials have produced inconsistent findings. Cranberries contain compounds that may prevent uropathogenic Escherichia coli (UPEC), a common cause of UTIs, from attaching to cells lining the urinary tract.

The study included 152 healthy women aged 21 to 65, with 150 completing the intervention. Participants avoided cranberry products and several other foods for 10 days before consuming 10 ounces of pure cranberry juice daily for four days.

Researchers collected urine samples before and after the intervention and measured anti-adhesion activity against P-type UPEC. This laboratory measure indicates how effectively urine can prevent bacteria from attaching to urinary tract cells.

Baseline anti-adhesion activity varied considerably between participants. After cranberry consumption, some women showed increased activity, while others showed little or no change.

Among women classified as having lower baseline anti-adhesion activity, 34.2% showed a positive response to cranberry juice, compared with 18.9% of those with higher baseline activity.

The researchers also found substantial differences in the urinary metabolic profiles of women with high and low anti-adhesion activity. Overall, 165 metabolic features differed between the groups. Some compounds were associated with greater anti-adhesion activity, including metabolites related to dietary polyphenols.

However, the study did not measure whether participants actually developed UTIs. It examined only laboratory anti-adhesion activity against one type of UPEC and involved a short, four-day intervention.

Therefore, the findings do not establish that cranberry juice prevents UTIs or identify which women would benefit clinically. Larger randomised trials are needed to determine whether metabolic profiles can predict individual responses to cranberry products and improve personalised UTI prevention.

REFERENCE: Li, S., Kamat, M., Taft, D. H., et al. (2026). Metabolic Phenotyping Identifies Distinct Urinary Anti-Adhesion Phenotypes and Differential Responses to Cranberry Juice Intake in Healthy Women. Nutrients. DOI: https://doi.org/10.3390/nu18193250.