Green tea is a popular hot or cold drink and contains less caffeine than a comparable quantity of brewed coffee. The antioxidants in green tea are believed to protect against cardiovascular disease and certain cancers, while the tea's caffeine content can give you a brief energy boost. Green tea extract is marketed as a dietary supplement -- and is included in many over-the-counter weight-loss supplements -- for its purported metabolism-boosting effects. However, green tea can have an aggravating effect on the bladder. Consult your doctor for advice regarding new or unusual urinary symptoms.
The Interstitial Cystitis Network publishes information regarding which foods and drinks are most and least likely to irritate the bladder. The information is intended for patients with the chronic bladder condition interstitial cystitis, but the categorization of safe and risky foods for the bladder holds true for the general population. The Interstitial Cystitis Network indicates that green tea is one of the beverages most likely to aggravate your bladder. Bladder-friendly alternatives include herbal teas such as chamomile or peppermint.
Urinary Tract Infections
Women and the elderly are at the greatest risk of experiencing one or more short-term infections of the urinary tract. During a UTI, you will likely experience urinary discomfort, urgency and frequency. The only way to get rid of a UTI is with antibiotics. According to MayoClinic.com, all caffeinated drinks can aggravate your bladder during a UTI -- you should avoid green tea and coffee, and instead drink plenty of water.
Over-consumption of Fluids
Drinking too much fluid can aggravate your bladder by making your urinary system work too hard. In a day, fluid consumption of between 60 and 64 fluid ounces is considered optimal for a healthy adult. The lower end of this scale would equate to five drinks at the "tall" Starbucks size, while the upper end would represent four of the "grande" Starbucks drinks. Bladder aggravation is less likely if you drink many small beverages throughout the day, rather than a few large drinks.
Caffeine and the Bladder
Caffeine, which is present in green tea as well as black tea and coffee, can aggravate the bladder. MayoClinic.com indicates that caffeine can cause bladder spasms, leading to aggravation and bladder control issues. Caffeine also acts as a diuretic, increasing your overall production and output of urine. Diuretics can aggravate the bladder and cause discomfort or problems controlling the bladder. As an alternative, consider decaffeinated green tea, which does not have the same diuretic effect as the caffeinated type.