Chamomile Benefits: What the Research Actually Shows

Chamomile has a reputation that runs well ahead of its evidence. It's the default bedtime tea across most of the Western world, sold and shelved and gifted on the assumption that it does something specific for sleep.

The research is more interesting than that, and more mixed. Some of what chamomile is famous for holds up under scrutiny. Some of it doesn't. And the single most-repeated claim about it — that it helps with insomnia — is the one with the weakest support.

Here's the honest picture.

The Position of the National Institutes of Health

The starting point for any honest read is the National Center for Complementary and Integrative Health, part of the NIH. Its assessment is blunt: studies of chamomile's effectiveness for a variety of specific conditions have not produced sufficient reliable evidence to rate clinical usefulness.

NCCIH also flags a structural problem that runs through this literature. Many studies test products containing chamomile plus other herbs, which makes it difficult to know what chamomile itself contributed. When you see a positive result for a "calming blend," that result belongs to the blend.

A second structural note, covered in more depth in our comparison of German and Roman chamomile: NCCIH's fact sheet covers German chamomile (Matricaria chamomilla) specifically, because that's where the research sits. Findings don't automatically transfer to the other plant sold under the same name.

Sleep: The Distinction That Changes Everything

This is where most coverage of chamomile goes wrong, in both directions.

The most substantial synthesis available is a 2019 systematic review and meta-analysis published in Phytotherapy Research by Hieu and colleagues, which searched eleven databases and pooled twelve randomized controlled trials. It examined four outcomes, and the results split cleanly.

On insomnia, only one qualifying RCT existed, and it found no significant change in insomnia severity index scores. That's it. One study, null result. NCCIH summarizes this same finding: there's very little information on chamomile's effect on insomnia, and the one study that exists found no benefit.

On sleep quality, the picture reverses. Pooling across trials, the review found a statistically significant improvement in sleep quality with chamomile — a standardized mean difference of −0.73 (95% CI −1.23 to −0.23, P < 0.005). That's a moderate effect size, and it's a real finding.

These are not contradictory results. They're measuring different things. Insomnia is a clinical sleep disorder with diagnostic criteria. Sleep quality is how well people report sleeping. Chamomile appears to move the second without addressing the first.

That distinction is worth holding onto, because it explains why chamomile's reputation persists despite thin clinical support. People who drink it do report sleeping better. That experience is real and it shows up in the data. It just isn't the same as treating a sleep disorder, and no product should imply otherwise.

Anxiety: Depends Which Kind

The same 2019 meta-analysis split anxiety into two categories, with two different answers.

State anxiety — situational, in-the-moment nervousness — showed no benefit. Pooling three RCTs produced a standardized mean difference of −0.15 (95% CI −0.46 to 0.16, P = 0.42). No effect.

Generalized anxiety disorder — the persistent clinical condition — did show improvement. Measured on the Hamilton Anxiety Rating Scale, chamomile produced a significant improvement at two weeks (mean difference −1.43, 95% CI −2.47 to −0.39, P = 0.007) and at four weeks (mean difference −1.79, 95% CI −3.14 to −0.43, P = 0.0097).

NCCIH's independent read aligns: some preliminary studies suggest a chamomile dietary supplement might be helpful for generalized anxiety disorder and associated depression.

Two caveats that matter a great deal here. First, the effect sizes are modest — a mean difference of roughly 1.4 to 1.8 points on the HAM-A scale is a real change but not a dramatic one. Second, and more importantly for anyone reading this on a tea company's website, these trials used standardized chamomile extracts at controlled doses, not cups of tea. A concentrated capsule and a brewed infusion are not the same intervention, and results from one do not transfer to the other.

Mouth and Digestive Findings

NCCIH notes two further areas where small studies have found something.

Oral rinses. Small studies suggest mouthwashes containing chamomile might prevent or treat swelling and irritation in the mouth resulting from radiation therapy, chemotherapy, or stem cell transplantation. This is a topical, clinical application — not a tea outcome.

Digestive and pediatric uses. Some research has found that products containing certain herb combinations that include chamomile may benefit diarrhea in children and infants with colic. NCCIH is explicit about the limitation: chamomile alone has not been shown to be helpful for these conditions. The positive results belong to the combinations.

Why the Evidence Base Is So Thin

Chamomile is one of the most consumed herbal infusions in the world, which makes the modesty of its research base genuinely surprising. A few reasons:

It's cheap and unpatentable. There's little commercial incentive to fund large trials on a plant anyone can grow.

Preparations vary enormously. Trials use standardized extracts, capsules, tinctures, and teas at wildly different concentrations. Pooling them is difficult and often inappropriate.

Blends confound everything. Chamomile is rarely consumed alone in commercial products, and study designs reflect that.

Outcomes are subjective. Sleep quality and anxiety are measured by self-report scales, which are legitimate instruments but noisier than an objective biomarker.

None of this means chamomile does nothing. It means the research hasn't been done at the scale its popularity would suggest.

Population-Specific Notes

Pregnancy and breastfeeding. NCCIH states that little is known about whether chamomile is safe during pregnancy or while breastfeeding. This is an absence of evidence rather than evidence of harm, but it's a meaningful absence. Talk to your provider.

People with allergies to the daisy family. Allergic reactions to chamomile are more likely in people allergic to related plants such as ragweed, chrysanthemums, marigolds, or daisies. Reported reactions include severe hypersensitivity and, rarely, anaphylaxis.

People taking medication. NCCIH reports interactions between chamomile and warfarin, and with some drugs metabolized by the liver, with theoretical reasons to suspect interactions with sedatives as well.

People taking birth control, or with estrogen-sensitive conditions. Chamomile may have some estrogen-like effects. Preliminary studies suggest taking chamomile alongside birth control pills might decrease their effectiveness, and chamomile might worsen conditions sensitive to estrogen exposure, such as breast or uterine cancer.

Children. Combination products including chamomile have been studied in children for colic and diarrhea, but chamomile alone hasn't been shown effective for these. Talk to a pediatrician first.

Key Takeaways

• The strongest finding is improved subjective sleep quality (SMD −0.73, P < 0.005 across pooled RCTs) — not treatment of insomnia, which showed no benefit in the single trial examining it.
• Generalized anxiety disorder showed modest significant improvement at 2 and 4 weeks; state anxiety showed none.
• Nearly all positive trial evidence used standardized extracts at controlled doses, not brewed tea.
• NCCIH's overall position is that the evidence is insufficient to rate clinical usefulness for any specific condition.
• Chamomile is well tolerated in trials, with the main real-world risks being Asteraceae allergy and drug interactions.

What This Means If You Drink It

Chamomile is a gentle, caffeine-free, genuinely pleasant botanical with several thousand years of continuous use behind it. Drinking a warm cup in the evening is a good ritual, and the sleep-quality data suggests people who do it tend to report sleeping better.

What it isn't is a treatment. It doesn't treat insomnia, it isn't a sedative, and the anxiety findings came from concentrated extracts rather than tea. We'd rather say that plainly than let a comfortable assumption do the selling.

Frequently Asked Questions

Does chamomile tea help you sleep?

The evidence supports improved self-reported sleep quality, not treatment of insomnia. A 2019 meta-analysis found a significant improvement in sleep quality across pooled trials, but the single trial on insomnia found no significant effect.

Is chamomile a sedative?

Not in any clinically established sense. It's often described that way, but the research doesn't support characterizing it as a sedative, and NCCIH does not.

Does chamomile help with anxiety?

It depends on the type. Pooled trials found no effect on situational (state) anxiety, but a modest significant improvement in generalized anxiety disorder at two and four weeks. Those trials used standardized extracts.

How much chamomile would I need to match the studies?

That question can't be answered cleanly, which is itself the point. Trials used standardized extracts at controlled doses, and there's no established conversion between a capsule of concentrated extract and a cup of brewed flowers.

Is chamomile safe to drink daily?

NCCIH considers chamomile likely safe when used orally in the amounts commonly found in teas and foods. The exceptions worth taking seriously are daisy-family allergies, regular medication use, pregnancy, and breastfeeding.

Why do so many products claim chamomile helps sleep?

Because the traditional and cultural association is very old and very strong, and because sleep-quality findings are real even though insomnia findings aren't. The gap between those two things is where most marketing lives.

Does chamomile interact with medications?

NCCIH reports interactions with warfarin and with some drugs metabolized by the liver, plus theoretical concerns with sedatives and possible reduction in birth control effectiveness. Check with your provider if you take anything regularly.

Related Reading

• German vs. Roman Chamomile: What's the Difference?
• Echinacea Benefits: What the Research Actually Shows
• Traditional Herbal Use vs. Clinical Evidence: Lavender's EMA Classification

Sources

• National Center for Complementary and Integrative Health, National Institutes of Health. Chamomile: Usefulness and Safety. Last updated November 2024.
• Hieu TH, Dibas M, Surya Dila KA, et al. Therapeutic efficacy and safety of chamomile for state anxiety, generalized anxiety disorder, insomnia, and sleep quality: a systematic review and meta-analysis of randomized trials and quasi-randomized trials. Phytotherapy Research. 2019;33(6):1604-1615.
• Amsterdam JD, Li QS, Xie SX, et al. Putative antidepressant effect of chamomile (Matricaria chamomilla L.) oral extract in subjects with comorbid generalized anxiety disorder and depression. Journal of Alternative and Complementary Medicine. 2020;26(9):813-819.
• Zick SM, Wright BD, Sen A, et al. Preliminary examination of the efficacy and safety of a standardized chamomile extract for chronic primary insomnia: a randomized placebo-controlled pilot study. BMC Complementary and Alternative Medicine. 2011;11:78.
• Dai Y-L, Li Y, Wang Q, et al. Chamomile: a review of its traditional uses, chemical constituents, pharmacological activities and quality control studies. Molecules. 2022;28(1):133.

This article is for educational purposes only and is not intended as medical advice. Chamomile is not a treatment or cure for any condition. Talk with your healthcare provider before using chamomile, especially if you are pregnant, nursing, taking medication, or considering it for a child.