Increased daily water intake protects against recurrent cystitis in premenopausal women who drink low volumes of fluid daily, a recent study found. The randomized, open-label, controlled 12-month trial included 140 healthy women with recurrent cystitis. Participants were randomly assigned to drink, in addition to their usual fluid intake, 1.5 L of water daily (water group) or no additional fluids (control group) for 12 months. Assessments of daily fluid intake, urinary hydration, and cystitis symptoms were performed at baseline, 6- and 12-month visits, and monthly telephone calls. Researchers found:

• The mean age of the 140 study participants was 35.7 years, and the mean number of cystitis episodes in the previous year was 3.3.
• Cystitis episodes were significantly less frequent in women who drank more water for 12 months compared with women who maintained their usual fluid intake.
• Overall, there were 327 cystitis episodes, 111 in the water group and 216 in the control group.
• The mean number of antimicrobial regimens used to treat cystitis episodes was 1.9 in the water group and 3.6 in the control group, with a difference in means of 1.7.