Kidney stones are a painful condition that comes about when calcium oxalate and other salts in urine form crystals or "stones." Approximately 5 percent of the world's population suffers from kidney stones. According to the University of Maryland Medical Center, green tea can be beneficial in the prevention of certain kinds of kidney stones. As with any new therapy, you should talk to your doctor to diagnose your problem before starting treatment, the UMMC cautions.
New Research
Research published by the "Royal Society of Chemistry Journal" indicates that at Sichuan University in Chengdu, China, scientists have discovered a reason why green tea might be able to prevent kidney stones from forming. The scientists examined green tea under microscopes to understand the interaction between green tea extract and calcium oxalate -- one main component of certain types of kidney stones.
Findings
Green tea is high in antioxidants, which have anti-cancer properties, but the Chinese researchers also found an important substance called phenols in green tea. Phenols appear to bind to calcium oxalate and alter the shape of the crystal. The new shapes are far less able to clump together and form kidney stones, the researchers stated.
Causes of Kidney Stones
The UMMC reports kidney stones can result from intestinal problems, a urinary tract infection or an inherited disorder. If the small bowel absorbs too much calcium or other minerals, it can increase your risk of developing a kidney stone. For people who have a family history of stones, it is particularly important to drink adequate fluids and exercise. In about 85 percent of cases, kidney stones are small enough to pass during urination, reports the UMMC. Researchers think green tea can inhibit the clumping of oxalate crystals, therefore making stones easier to pass.
Further Benefits of Green Tea
In addition to promising preliminary research regarding green tea and kidney stones, green tea has been used to aid in weight loss and lower cholesterol levels, according to the National Institutes of Health.
Recommendations
Between 240,000 and 720,000 Americans suffer from kidney stones every year and the prevalence is four times as high for men than women. According to the UMMC, "The stones grow slowly over several months or years and are made of hard deposits of various minerals, including calcium, uric acid and oxalate." Adding green tea in supplement form or steeped as a tea may be beneficial in the prevention of new stones. Another way to prevent stones is to reduce high oxalate foods, "such as spinach, rhubarb, beets, nuts, chocolate, coffee, black tea, wheat bran, strawberries and beans," the UMMC states.
