Evidence of the Impact of Diet, Fluid Intake, Caffeine, Alcohol and Tobacco on Lower Urinary Tract Symptoms: A Systematic Review.

PURPOSE: Diet, fluid intake and caffeine, alcohol and tobacco use may have effects on lower urinary tract symptoms. Constructive changes in these modifiable nonurological factors are suggested to improve lower urinary tract symptoms. To better understand the relationship between nonurological factors and lower urinary tract symptoms, we performed a systematic literature review to examine, grade and summarize reported associations between lower urinary tract symptoms and diet, fluid intake and caffeine, tobacco and alcohol use. MATERIALS AND METHODS: We performed PubMed® searches for eligible articles providing evidence on associations between 1 or more nonurological factors and lower urinary tract symptoms. A modified Oxford scale was used to grade the evidence. RESULTS: We reviewed 111 articles addressing diet (28 studies), fluid intake (21) and caffeine (21), alcohol (26) and tobacco use (44). The evidence grade was generally low (6% level 1, 24% level 2, 11% level 3 and 59% level 4). Fluid intake and caffeine use were associated with urinary frequency and urgency in men and women. Modest alcohol use was associated with decreased likelihood of benign prostatic hyperplasia diagnosis and reduced lower urinary tract symptoms in men. Associations between lower urinary tract symptoms and ingestion of certain foods and tobacco were inconsistent. CONCLUSIONS: Evidence of associations between lower urinary tract symptoms and diet, fluid intake and caffeine, alcohol and tobacco use is sparse and mostly observational. However, there is evidence of associations between increased fluid and caffeine intake and urinary frequency/urgency, and between modest alcohol intake and decreased benign prostatic hyperplasia diagnosis and lower urinary tract symptoms. Given the importance of these nonurological factors in daily life, and their perceived impact on lower urinary tract symptoms, higher quality evidence is needed.