A new report suggests that limiting intake of caffeinated beverages may help stave off troublesome bladder and urinary symptoms. Many women and men live with symptoms affecting the lower urinary tract, such as frequent or urgent urination, needing to get up multiple times at night to urinate, and problems with voiding, such as a weak urinary stream or failure to empty the bladder completely. Dietary advice for people with these symptoms often includes avoiding caffeinated, carbonated, and citrus beverages because these drinks can irritate the bladder and therefore might also contribute to lower urinary tract symptoms; however, direct evidence for this association is limited. The Boston Area Community Health Survey (BACH) is a population-based study in white, Hispanic, and non-Hispanic black adults designed to assess prevalence and determinants of urological symptoms. Researchers analyzed dietary and symptom data collected from over 4,000 BACH study participants at both study entry (baseline) and about five years later to see if they could uncover any relationships between types and amounts of beverages (coffee, juice, and carbonated soda, including diet sodas and decaffeinated/caffeine free coffee and soda) and several lower urinary tract symptoms. They found that men reporting higher average caffeinated coffee or total caffeine consumption in the year prior to baseline—e.g., more than two cups of coffee per day versus none—had a greater likelihood of symptom progression five years later, particularly symptoms of frequency and urgency. Drinking citrus juice, however, was associated with lower risk of symptom progression in men.
When they looked at changes in beverage consumption, the researchers found that women and men who increased their total coffee intake by at least two servings per day between baseline and the five year follow-up were more likely to have progression of urgency and frequency symptoms compared to those who had smaller changes in consumption; also, women who increased their total consumption of soda by at least two servings per day were more likely to have worsening of urgency symptoms. The researchers also examined short-term relationships between beverage intake and symptoms, and found that women and men who drank more than two cups of coffee or soda per day within the week prior to symptom assessment were more likely to have symptoms than those who did not; caffeinated diet soda appeared to affect women’s symptoms at even lower consumption. While additional studies are needed to verify these observations, the findings support current recommendations about limiting coffee and soda intake to help manage lower urinary tract symptoms and suggest that there are dietary components to be further explored for how they may cause urologic symptoms or, in the case of citrus juice consumption by men, possibly provide protection.