Folklore has for years perpetuated the use of cranberry for the treatment and prevention of urinary tract infections (UTIs). Cranberries can be consumed as fresh fruit, concentrate, sauce, and juice. Cranberry juice cocktail, which is a mixture of cranberryjuice, sweetener, water, and vitamin C, has been used in a number of studies since single-strength juice is unpalatable.
Basic science research has suggested that the cranberries may inhibit the adherence of Escherichia coli to urinary tract epithelial cells (11). This effect may also extend to other bacteria (12). It is still unclear as to exactly what properties of cranberries account for such activity, although recent studies have suggested that proanthocyanidins (also found in blueberries) are the compounds probably responsible (13).
To date, no high-quality clinical trials have been done to suggest the efficacy of cranberry juice or extract for the treatment of UTIs (14). In one uncontrolled trial done in the 1960s, 73% (44 of 60) of patients had some improvement in symptoms or reduction in culture growth after 21 days of consuming 16 oz of cranberry juice. However, only four patients had completely negative cultures. Furthermore, most of the 44 patients who showed some response had a recurrence within 6 weeks of stopping therapy, suggesting that cranberryjuice may be inadequate for eradication of actual infections (15).
A number of studies have suggested that cranberryjuice may be effective as prophylaxis against UTIs [16-19]. One double-blind trial of 153 elderly women randomized to consuming 300 mL of cranberry juice cocktail or pla cebo juice showed a significant reduction in the frequency of bacteriuria with pyuria (17). The quality of this trial has been questioned owing to baseline differences between the two groups (20). Subsequent trials, however, have also suggested such a benefit (18,19). A positive effect has not been seen in children managed by intermittent bladder catheterization (21,22).
Ingestion of cranberry is generally considered quite safe. Some concern over the potential for development of nephrolithiasis exists due to increases in urinary oxalate with regular consumption (23). The clinical significance of this finding is unclear. No significant drug interactions have been documented to date.
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Acai, Maqui And Many Other Popular Berries That Will Change Your Life And Health. Berries have been demonstrated to be some of the healthiest foods on the planet. Each month or so it seems fresh research is being brought out and new berries are being exposed and analyzed for their health giving attributes.