Does cranberry have a role in catheter-associated urinary tract infections?
Cranberry was effective in reducing the number of symptomatic CA-UTIs in all patients (n=22). Resistance to antibiotics was reduced by 28%. Furthermore, colony counts were reduced by 58.65%.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5698020/
Dosage effect on uropathogenic Escherichia coli anti-adhesion activity in urine following consumption of cranberry powder standardized for proanthocyanidin content: a multicentric randomized double-blind study.
To prevent UTIs, inhibition of bacterial adhesion to epithelial cell lining is proven with 36 mg of PAC (proanthocyanidins Type A) a day.
For maximum efficacy to protect against bacterial adhesion, 72 mg of PAC (double-dose) may be taken for 2 days.
https://www.ncbi.nlm.nih.gov/pubmed/20398248
Cranberries for preventing urinary tract infections.
An updated Cochrane review of studies which determined that cranberry juice for the prevention of UTIs cannot be recommended.
It was identified that all studies did not utilize a standardized method of introduction (juice, capsule, pill) or to ensure the potency, and confirm they contained an adequate amount of the ‘active ingredient’ (36 mg PAC) for use in patients with recurrent UTIs.
https://www.ncbi.nlm.nih.gov/pubmed/23076891