Kidney stones form from chemicals and acids in the urine. The mass of crystals that results will eventually be passed out of the body and may cause severe pain. Since kidney stones are likely to recur, prevention is important. Both tea and lemon may be helpful in the prevention of kidney stones.
Kidney Stones
There are several different types of kidney stones. The most common is the calcium-based stone, in which calcium combines with either oxalate or phosphate. Struvite stones contain magnesium and ammonia; they may result from an infection. Uric acid stones, as the name implies, contain uric acid. The last type of stone is the relatively rare cystine stone.
Lemons and Citric Acid
Lemons contain citric acid or citrate, which is the same substance in urine that helps to keep it acidic. Lemons and lemon juice, according to a study published in the March 2008 "Journal of Endourology," are high in citric acid. Lemon juice may contain almost six times more citric acid than other forms of citrus juice, and an article in the summer 2009 issue of "Reviews in Urology" reported a number of studies in which lemonade was effective in raising urinary citrate levels.
Lemonade Therapy
Lemonade is a preventive measure for recurring kidney stones, according to Roger L. Sur, medical director of UC San Diego Comprehensive Kidney Stone Center. Sur recommends lemonade therapy consisting of four ounces of lemon juice in two liters of water per day. Sur reports that this therapy decreased the risk of stone formation from 1.00 to 0.13 stones per patient. Lemonade therapy is most effective for calcium-based stones.
Tea and Kidney Stones
Drinking black or green tea each day could reduce the risk of kidney stones, according to the MayoClinic.com. A heavily-cited older study published in the 1996 "Journal of Epidemiology" reported that tea decreased the risk of recurrent kidney stones in men age 40 to 75 by 14 percent. A more recent study of green tea and kidney stones in the November 2009 online journal "CrystEngComm" reported that green tea prevented calcium oxalate stones from forming into clumps that could result in a kidney stone.
Considerations and Warnings
Although a daily cup of tea -- with or without lemon juice -- is safe for most people, kidney stones should not be self-managed. Tea does contain caffeine so if you are sensitive to caffeine's effects, choose a decaffeinated version. If you have questions or concerns, consult a health care professional.
References
- Crstengcomm; Modulation of Calcium Oxalatecrystallization by Commonly Consumed Green Tea; Zhenhua Chen, et.al.; November 2009
- "American Journal of Epidemiology"; Prospective Study of Beverage Use and the Risk of Kidney Stones; Gary C. Curhan, et.al.; 1996
- National Kidney & Urologic Diseases Information Clearinghouse; What I Need To Know About Kidney Stones; John Asplin, M.D., et.al.; January 2009
- "Journal of Endourology"; Quantitative Assessment of Citric Acid in Lemon Juice, Lime Juice, and Commercially-Available Fruit Juice Products; Kristina L. Penniston, M.D., et.al.; March 2008
- "Reviews in Urology"; Hypocitraturia: Pathophysiology and Medical Management; Jack M Zuckerman, BS and Dean G Assimos, MD; Summer 2009
- University of California at San Diego; Five Ways to Prevent Kidney Stones: From Lemonade to Surgery; Jackie Carr; April 22, 2010
