Is Kombucha good for kidney stones? Kombucha is a fermented tea rich in probiotics and antioxidants, which may support digestion and overall hydration. Proper hydration can help reduce the risk of kidney stone formation. However, kombucha is acidic and may contain oxalates, which can be harmful for some kidney stone patients. People with kidney stones should consume kombucha in moderation and consult a healthcare professional before adding it to their diet.