Benefits
Urinary tract health: cranberry research in women with past infections
Across 26 pooled randomized trials (6,211 people), cranberry products lowered the risk of symptomatic, culture-verified urinary tract infections by about 30% (moderate certainty), including in women with recurrent infections (RR 0.74). Care-home residents, pregnant women and people with bladder-emptying problems showed little or no reduction. None of these trials tested Exocyan, and the one Exocyan study had no placebo group.
FDA qualified claim for 500 mg cranberry powder
Since July 2020 the FDA allows cranberry supplements with at least 500 mg of 100% cranberry fruit powder daily to say they may help reduce the risk of recurrent urinary tract infection in healthy women, with a statement that the supporting evidence is limited. Nexira names Exocyan 10G and 10G Bio as meeting this amount. A qualified claim is a lower standard than an authorized health claim.
PAC dose and standardization
A pooled analysis of 10 trials found that at least 36 mg of PACs a day lowered urinary tract infection risk by 18% (RR 0.82), while lower intakes showed no significant effect, and benefit appeared only with 12 to 24 weeks of use. The PACCANN trial of a different extract (37 versus 2 mg PACs a day) missed its primary outcome, and the Cochrane review found no clear difference between PAC doses.
E. coli anti-adhesion (laboratory mechanism)
In laboratory studies, cranberry proanthocyanidins stop P-fimbriated E. coli from sticking to cells lining the bladder. In a juice trial in women with recent infections, P-fimbriated E. coli made up 43.5% of urine isolates on cranberry versus 80.0% on placebo (P=0.07), in line with this idea but not statistically significant.
Gum health in a small trial of an apparent Exocyan grade
In a 21-day trial in 20 dental students who stopped oral hygiene, a dissolving tablet of 90 mg 'exocian cran 408' (36 mg OPCs) plus 120 mg vitamin C lowered gum inflammation and bleeding versus placebo, but plaque scores were higher. LACER S.A. financed the trial. This is a single small trial and has not been repeated.
Identity testing by the maker
Nexira states it developed a proprietary universal analysis method to confirm the identity and quality of Exocyan and uses several PAC methods (BL-DMAC, Bate-Smith and HPLC). This is a manufacturer statement; no published study of the method is cited here.
High PAC concentration
Nexira lists grades reaching 90% PACs by the Bate-Smith method or 20% by BL-DMAC, so a given PAC dose needs less powder. Because the two methods give very different numbers for the same material, PAC percentages can only be compared when the method is stated.
Mechanism of action
PAC anti-adhesion of uropathogenic E. coli
Cranberry proanthocyanidins inhibit the adherence of P-fimbriated E. coli to the cells lining the bladder in laboratory studies. A juice trial found fewer P-fimbriated E. coli in urine isolates on cranberry, though the difference was not statistically significant.
Two ways of measuring PACs
PAC content can be measured by BL-DMAC or by the Bate-Smith method, and they give different results for the same extract: Nexira reports up to 90% by Bate-Smith and 20% by BL-DMAC. When comparing products or matching a studied PAC dose, check which method the label uses.
Streptococcus mutans biofilm inhibition (oral)
In laboratory studies, cranberry PACs inhibit glucosyltransferase (Gtf) activity in Streptococcus mutans, the enzyme that turns dietary sucrose into the polysaccharide matrix of dental plaque biofilm. In lab and rat models, topically applied PACs reduced biofilm formation and caries, and specific A-type PAC oligomers (dimers to dodecamers) inhibited GtfB. Neither dental trial on this page measured Gtf.
Clinical trials
Prospective, open-label observational study without a placebo group (NCT04962971), comparing Exocyan Cran 40SD (373 mg/day), Exocyan Cran 40G (404 mg/day) and Exocyan FG (2,090 mg/day), each giving 162 mg of total PACs a day, for 6 months; funded by Nexira, with a Nexira employee as first author (Guillemet et al. 2026, Res Rep Urol).
219 women aged 18 to 65 with recurrent urinary tract infections; 217 in the safety analysis and 202 in the effectiveness analysis.
In all three groups urinary comfort scores rose (53.8 to 80.9 on a 100-point scale) and the average number of symptomatic episodes fell (2.9 to 0.8), with no significant differences between extracts; the 40G group did better on some secondary scores. Baseline episodes were recalled at enrolment and there was no placebo group, so the authors said randomized controlled studies are needed. 13 of 217 women reported non-serious, mainly digestive, side effects.
Double-blind randomized controlled trial (NCT02572895) of Urophenol™ cranberry extract, made by Nutra Canada (now part of Diana Food Canada), which co-funded the trial; not Exocyan. 2 x 18.5 mg PACs/day versus a low-dose control of 2 x 1 mg PACs/day for 24 weeks (Babar et al. 2021, BMC Urol).
145 healthy women aged 18 or over with at least 2 urinary tract infections in 6 months or 3 in 12 months.
The primary outcome was null: the high dose produced a non-significant 24% reduction in symptomatic urinary tract infections versus the low dose (incidence rate ratio 0.76, 95% CI 0.51 to 1.11). A post-hoc subgroup of 97 women with fewer than 5 infections in the prior year did show a significant decrease, which is hypothesis-generating only. The comparator was a low PAC dose, not a true placebo.
Fifth update of the Cochrane review: 50 randomized trials, 26 of the 45 placebo or no-treatment trials pooled for symptomatic, culture-verified infections, stratified by population (Williams et al. 2023, Cochrane Database Syst Rev).
8,857 participants across 50 randomized trials.
Cranberry products reduced overall infection risk by 30% (RR 0.70, 95% CI 0.58 to 0.84; moderate certainty; 6,211 participants). Women with recurrent infections RR 0.74 (95% CI 0.55 to 0.99; 8 studies), children RR 0.46 (5 studies), people susceptible after an intervention RR 0.47 (6 studies). There may be little or no benefit in elderly institutionalized people or pregnant women (moderate certainty) or adults with neuromuscular bladder dysfunction (low certainty).
Meta-analysis of 10 randomized controlled trials of cranberry products with reported daily PAC intake, stratified by PAC dose (at least 36 mg/day versus less) and duration (Xiong et al. 2024, Front Nutr).
Participants of 10 randomized trials with PAC-quantified cranberry products.
Daily PAC intake of at least 36 mg reduced infection risk by 18% (RR 0.82, 95% CI 0.69 to 0.98, p=0.03); less than 36 mg showed no significant effect (p=0.39). The reduction was significant only with 12 to 24 weeks of use (RR 0.75, p=0.004) and in female-only subgroups (RR 0.84, p=0.02). The Cochrane review found no clear difference between PAC doses (very low certainty).
Double-blind, randomized parallel-group trial of a 0.6% cranberry mouthwash (made by the investigators from a Mehta Pharmacy extract; PAC content not reported; it contained zinc chloride, as did the chlorhexidine rinse) versus 0.2% chlorhexidine, 10 mL twice daily for 14 days (Khairnar et al. 2015, Contemp Clin Dent).
50 dental students aged 18 to 20, randomized into two groups of 25.
Streptococcal counts in plaque fell 68% with cranberry and 69% with chlorhexidine over 14 days, with no significant difference between the rinses; that does not prove the two are equivalent. Glucosyltransferase activity was not measured.
Prospective double-blind randomized controlled trial: a dissolving tablet of 90 mg 'exocian cran 408' (apparently an Exocyan grade; 36 mg OPCs) plus 120 mg vitamin C, or placebo, for 21 days, financed by LACER S.A. (Díaz Sánchez et al. 2017, Mediators Inflamm).
20 healthy dental students at the University of Seville, 10 per group; gingivitis was induced by stopping all oral hygiene for 21 days after cleaning.
The Silness-Löe gingival index was twofold higher in controls at day 14 and 50% higher at day 21 (p<0.0001), and gum bleeding was lower with the supplement (p<0.005). However, plaque on the tooth surface (Turesky index) was 33% higher in the supplement group at day 14 (p<0.006) and about double at day 21 (p<0.0001).