No, chamomile tea is not known to cause kidney stones and is often recommended as a safe.
The idea that tea contributes to kidney stones makes sense on the surface. Black tea contains oxalates, natural compounds that can bind with calcium in the urine and potentially form crystals. Many people hear “tea has oxalates” and start wondering whether every cup is a gamble.
Chamomile tea is a different story. It’s an herbal infusion made from flowers, not the tea plant, and its oxalate profile is dramatically lower than black or green tea. Hospital dietary guidelines for kidney stone prevention actually list chamomile as a safe, hydrating option. Here’s what the evidence says about the connection between chamomile tea and kidney stones.
How Oxalates Work in the Body
Oxalates are organic compounds found naturally in many plant foods, including spinach, rhubarb, beets, and certain teas. In sensitive individuals, oxalates can bind to calcium in the urinary tract, forming tiny crystals that may grow into calcium oxalate stones — the most common type of kidney stone.
A low-oxalate diet, typically defined as less than 40 to 50 mg of oxalates per day, is a standard first-line recommendation for recurrent calcium oxalate stone formers. This diet usually limits black tea, dark beer, and chocolate milk, but it does not necessarily restrict herbal teas.
The key detail is that not all teas are chemically alike. Black and green teas are made from the leaves of Camellia sinensis, which contains moderate to high oxalate levels. Herbal teas are infusions of flowers, roots, or fruits, and their oxalate content tends to be much lower.
Why Black and Green Tea Get Blamed (and Chamomile Doesn’t)
It’s common for people to generalize the risks of black tea to all types of tea. This is a logical shortcut, but the chemistry of chamomile doesn’t support the same concern.
- Black tea: Brewed black tea contains roughly 5 to 10 mg of oxalates per 8 oz cup, depending on steeping time and leaf quantity. This is considered a moderate level for stone formers.
- Green tea: Similar to black tea, green tea contains measurable oxalates, though generally slightly lower. Prolonged steeping can leach more oxalates into the water.
- Chamomile tea: An infusion of dried chamomile flowers. The oxalate content of the brewed tea is negligible in most analyses, making it a very low-risk choice for most people.
- Herbal fruit teas: Rooibos, mint, and fruit-based herbal teas also tend to have very low oxalate levels, providing a hydrating alternative.
- Iced black tea: Because people often drink larger volumes, iced black tea can contribute a significant oxalate load if consumed daily.
The distinction matters because hydration is actually protective against kidney stones. Swapping black tea for a hydrating, low-oxalate option like chamomile may offer the best of both worlds — fluid intake without the oxalate load that comes from traditional teas.
What the Research Says About Chamomile and Stones
There are no large-scale studies specifically investigating whether chamomile tea causes kidney stones. The evidence is indirect, coming from oxalate content analysis and general tea consumption studies.
A hospital patient-education PDF on kidney stones and diet specifically recommends chamomile tea as a safe alternative. WebMD also notes chamomile is generally safe, though drinking very large amounts regularly could cause side effects — it’s worth checking the chamomile tea side effects guide if you plan to drink it daily.
Interpretation of the numbers depends heavily on whether you’re looking at the dry herb or the brewed tea.
| Source | Reported Oxalate Level | Interpretation |
|---|---|---|
| Hospital Diet Guide (St. Joe’s) | Listed as a safe alternative | Low risk |
| Academic Study (PMC 2013) | <1 mg per 100 ml brewed | Negligible |
| OxalateGuard (dry herb) | 199.1 mg per 8 oz (dry) | Moderate, but not brewed strength |
| Kidney Dietitian Resource | No studies found | Generally considered very low risk |
| Low-Oxalate Diet PDF | Herbal teas allowed freely | Safe for most stone formers |
The discrepancy in the numbers comes from one source measuring the dry herb and others measuring the brewed tea you actually drink. Standard brewing extracts far fewer oxalates than the dry weight suggests.
How to Enjoy Chamomile Tea If You Have Stones
For most people, drinking chamomile tea is a low-risk habit. If you’re managing existing stones or trying to prevent them, these steps can help you feel confident about it.
- Keep it moderate: Enjoying 1 to 3 cups of brewed chamomile tea per day fits within typical low-oxalate guidelines. There’s no need to restrict it unless your doctor advises otherwise.
- Brew it right: A standard 5-minute steep in 8 oz of hot water extracts flavor without excessively concentrating any compounds. Avoid over-steeping for long periods.
- Pair it with calcium: Eating calcium-rich foods alongside oxalate-containing foods can help oxalates bind in the gut rather than in the kidneys. Chamomile with a splash of milk is a fine choice.
- Stay hydrated overall: The biggest dietary factor for kidney stones is total fluid intake. Herbal teas count toward your hydration goals and may help lower overall risk.
Individual oxalate tolerance varies, and not everyone with stones needs to follow a strict low-oxalate diet. These are general guidelines that fit within most stone-prevention plans.
The Bigger Picture — Hydration and Diet
A 2021 prospective study found that tea consumption overall was associated with a lower risk of developing kidney stones, likely because the hydrating effect outweighs the oxalate risk for most people.
This study is a useful reminder that the relationship between diet and kidney stones is multifactorial. Sodium intake, animal protein consumption, calcium intake, and total fluid volume all play larger roles than any single beverage. The tea reduces kidney stone risk study adds weight to the idea that staying hydrated with low-oxalate fluids is a sound strategy.
Chamomile tea fits naturally into a stone-preventive diet because it is caffeine-free and provides antioxidants without a significant oxalate load.
| Beverage | Oxalate Level | Notes |
|---|---|---|
| Chamomile tea | Negligible | Naturally caffeine-free |
| Peppermint tea | Negligible | A good alternative |
| Lemon water | Very low | Citrate may help prevent stones |
| Plain water | Zero | Best for overall hydration |
The Bottom Line
There is no credible evidence linking moderate chamomile tea consumption to kidney stone formation. The available evidence, while indirect, suggests the risk is very low for most people. Chamomile is hydrating, naturally low in oxalates, and recommended by many hospital dietary guides for stone formers.
If you have a history of calcium oxalate stones or your doctor has recommended a specific low-oxalate target, a registered dietitian or nephrologist can help you figure out exactly where chamomile tea fits into your daily fluid plan.
References & Sources
- WebMD. “Supplement Guide Chamomile” WebMD notes that drinking too much chamomile tea could cause side effects, and advises consulting a doctor if planning to drink more than a cup or two per day.
- NIH/PMC. “Tea Reduces Kidney Stone Risk” A 2021 prospective study published in PMC found that tea consumption may reduce the risk of kidney stones, contrary to the idea that tea causes them.