Could Your Favorite Tea Be Causing Kidney Stones? Here’s What You Need to Know
The Surprising Link Between Tea and Kidney Stones
Tea is often praised for its antioxidants, calming properties, and role in heart health — but did you know that drinking too much of certain teas can raise your risk for kidney stones? Kidney stones are hard mineral deposits that form in the kidneys and can cause severe pain, nausea, and urinary issues.
The main culprit is oxalate, a naturally occurring compound found in many plant foods. When oxalate combines with calcium in your urine, it can form calcium oxalate stones — the most common type of kidney stone.
Teas Highest in Oxalates
Not all teas are created equal. The oxalate content varies widely, and some teas are much more likely to contribute to stone formation.
Black tea (regular iced tea, English breakfast)
Oxalate Content- High
Risk for kidney stone- Higher risk when consumed in large amounts
Green tea
Oxalate Content- Moderate
Risk for kidney stone- Lower risk but still something to monitor
Herbal teas (chamomile, peppermint, ginger)
Oxalate Content- Very Low to None
Risk for kidney stone- Kidney-friendly
Matcha (powdered green tea)
Oxalate Content- High (because you consume the whole leaf)
Risk for kidney stone- Can increase risk if consumed daily in large amounts
Did you know? One report described a man who drank a gallon of iced black tea every day and developed repeated kidney stones because of the high oxalate load.
Tips to Lower Your Risk
You don’t need to give up tea completely — just be mindful:
Moderate your intake: Limit black tea or matcha to 1–2 cups a day if you have a history of stones.
Stay hydrated: Drink plenty of water to dilute urine and flush out oxalates.
Balance with calcium-rich foods: Eating calcium (from dairy or fortified plant milk) with tea can help bind oxalate in the gut before it reaches the kidneys.
Choose herbal options: Chamomile, rooibos, ginger, and peppermint teas are great low-oxalate alternatives.
When to Talk to Your Provider
If you experience flank pain, blood in urine, or frequent urinary tract infections, it’s worth discussing with a healthcare professional. A simple urine test can check your oxalate levels and other risk factors.
Tea can be part of a healthy lifestyle, but overconsumption of high-oxalate teas may increase your risk for kidney stones. Moderation, hydration, and smart choices go a long way in protecting your kidneys.