Orange Juice Fights Kidney Stones
Orange Juice May Prevent Repeat Kidney Stones Better Than Some Other Citrus Drinks
Sept. 7, 2006 -- A glass of orange juice a day may keep kidney stones at bay.
A new study shows that a daily glass of orange juice may help prevent
recurrent kidney stones better than other citrus juices like lemonade.
Researchers say many people assume that all citrus juices prevent the
formation of kidney stones. But these results suggest not all citrus juices
have the same protective effect in people at risk for the painful
Kidney stones develop when minerals and other chemicals in the urine become
too concentrated. Over time, these crystals bind to form a stone.
People who have had a kidney stone are at high risk for recurrent stones and
are advised to make diet and lifestyle changes to slow the rate of new stones
Citrate Slows Kidney Stones
Studies have shown that potassium citrate supplements can slow the formation of kidney stones,
but some people can't tolerate the supplements because of gastrointestinal side
For those people, drinking citrus juices, which contain a natural form of
citrate, may offer an alternative to the supplements.
Citrate helps prevent kidney stone formation by allowing for more citrate in
the urine and decreasing the acidity of urine.
OJ Better Than Lemonade
In the study, researchers compared the effects of orange juice and lemonade
in preventing recurrent kidney stones. Both juices contain comparable citrate
Thirteen volunteers, some with a history of kidney stones and some without,
participated in the three-phase study.
In random order, the participants drank approximately 13 ounces of either
distilled water, orange juice, or lemonade three times a day with meals for one
week, with a three-week interval before moving to the next phase. They also
followed a special diet as recommended for preventing recurrent kidney
The results showed that orange juice increased levels of citrate in the
urine and decreased urine acidity, which reduced the risk of kidney stones. But
lemonade did not have the same effect.
"Orange juice could potentially play an important role in the management of
kidney stone disease and may be considered an option for patients who are
intolerant of potassium citrate," says researcher Clarita Odvina, MD, assistant
professor of internal medicine at the University of Texas Southwestern Medical
Center at Dallas, in a news release.
Odvina says additional ingredients in citrus juices may affect their
effectiveness in reducing the risk of developing new kidney stones. For
example, the citrate in orange and grapefruit juice is accompanied by a
potassium ion, while the citrate in lemonade and cranberry juice is accompanied
by a proton. She says the proton may counteract the acid-lowering effects of
The results appear in the Clinical Journal of the American Society of
Nephrology. Researchers say this was a small study and further research is
needed to evaluate the role of orange and other citrus juices in preventing
The study was supported by research grants from NIH.