American Chestnut Tree Leaf Tea for Mitigating Kidney Stone Disease Occurrence

doctor dominguez in a dark suit and white collared shirt. doctor donelan in a white lab coat with a blue collared shirt and tie. doctor tania queseda in a blue and white blouse.
Pictured Left to Right: Dr. Paul Dominguez-Gutierrez, Dr. William Donelan, Dr. Tania Quesada

*US Patent Pending

Reduces Oxalate Levels in Tea, Presenting a Potential New Kidney Stone Therapeutic for High-Risk Individuals

The leaves obtained from a genetically modified American Chestnut Tree (ACT) reduce oxalate levels in commercially available teas, when added, lowering the risk of kidney stone development in high-risk tea drinkers. Kidney stones affect about 10% of the U.S. population, costing over S10 billion to treat, annually. Many stone formers excrete excessive amounts of oxalate in their urine due to the over-ingestion of oxalate from dietary sources. Tea is high in soluble oxalate, and its intake is generally not advised in calcium oxalate kidney stone formers. The American chestnut tree, once considered the most important North American forest tree, had become functionally extinct due to the “chestnut blight,” caused by Cryphonetria parasitica, a fungus that secrets oxalic acid at lethal levels. However, in the 1990s, Darling 58, a transgenic ACT that overexpresses wheat oxalate oxidase to degrade oxalate and resist blight, was developed.

Drs. Paul Dominguez-Gutierrez, William Donelan and Tania Quesada at the University of Florida have discovered the addition of Darling 58 ACT leaves to commercially available teas reduces their oxalate levels. American Chestnut Tree leaves, alone or in combination with tea leaves, may serve as a potential therapeutic to reduce oxalate levels and mitigate renal stone occurrence in stone formers wanting to enjoy the health benefits of freshly brewed tea.

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