
Most of us love starting the day with a hot cup of tea. Whether it’s the classic chai with milk and spices or green tea, it’s a comforting ritual. But did you know that drinking too much tea could sometimes cause problems for your kidneys?
What’s the problem?

Tea contains something called oxalates — natural substances found in many plants. When you eat or drink a lot of oxalates, your body might have trouble getting rid of them. These oxalates can join with calcium in your urine and form kidney stones, which can be painful.
Black tea has a lot of oxalates. Some studies say drinking a lot — like 6 to 8 cups a day — can increase the chance of kidney stones. Green tea and herbal teas usually have fewer oxalates, but you still shouldn’t drink them like water.
Also See:Â Think All Nutritious Foods Are Good at Night? See What Experts Warn
A rare but serious case
In 2015, a man in the U.S. who drank 16 cups of iced tea a day developed kidney failure. This was a very rare case, but it shows that too much tea can be dangerous. The man consumed over 1,500 mg of oxalates daily, while experts recommend only 40-50 mg per day.
What about Indian chai?
Traditional masala chai uses black tea leaves but is boiled with milk, which contains calcium. The calcium can help stop oxalates from getting into your blood, making chai with milk a little safer than just black tea. So, your regular chai is not very risky if you don’t overdo it.
If you have had kidney stones before or a family history of them, it’s best to drink only 2-3 cups a day.
Is green tea better?
Green tea has less oxalate than black tea and is known for its antioxidants. But too much green tea, especially in supplements, can also cause kidney or liver problems. Balance is important.
Are there other risks from tea?
Some packaged or instant teas have extra additives like phosphorus or lots of salt, which are bad for people with kidney problems. If you have chronic kidney disease (CKD), it’s best to avoid teas with added sweeteners or flavors.
The takeaway
Drinking a moderate amount of tea (2-3 cups a day) is usually safe and can even be good for you. But if you:
- Have had kidney stones,
- Have kidney disease or risk for it,
- Drink more than 5-6 cups daily,
you should be careful with your tea habits. Try herbal teas, drink plenty of water, and listen to your body.
Your kidneys work hard to keep you healthy. Enjoy your tea, but don’t overdo it!