Chamomile tea: a pleasant cup with thin evidence behind it

A Cochrane review of 27 trials on period pain found one trial of 160 women in which chamomile extract lowered pain scores by 1.42 points more than NSAIDs (95% CI 1.15 to 1.69). The reviewers rated that evidence very limited and of very low to low quality. For anxiety, an international taskforce of 31 psychiatry experts from 15 countries weighed meta-analyses of trials and did not recommend chamomile for generalized anxiety disorder. Both judgements rest on extracts and capsules. We found no trial of the tea itself for sleep or anxiety. A 240 g cup of brewed chamomile tea carries about 2 calories, and the US database holds no figures for its plant compounds.

The numbers, per 3.5 oz (100 g)

As people eat it, per 3.5 oz (100 g)

How much is actually in it

• A standard 240 g cup of brewed chamomile tea carries about 2 calories in the US survey food database. — FNDDS food Tea, hot, chamomile (n = 1 food code) Evidence E source
  1 calories per 3.5 oz (100 g); 1 cup 240 g = 2.4 calories; small 360 g, medium 480 g, large 600 g

What your body absorbs

• In adults eating a bread meal, a serving of camomile tea cut non-heme iron absorption by 47%, less than black tea at 79-94% or peppermint at 84%. — adult human subjects, bread meal with test beverages (n = not stated in abstract) Evidence C source
  Camomile -47%, lime flower -52%, vervain -59%, black tea -79 to -94%, peppermint -84%
• In 13 women, iron absorption from fortified bread was not significantly different whether eaten alone or with a chamomile infusion sweetened with panela. — 13 women, ferrous sulfate fortified wheat bread (n = 13) Evidence B source
  No significant difference (8% absorption reported)

What it does to your health

• A Cochrane review of 27 trials found only very limited, low quality evidence from one trial of 160 women that chamomile eased period pain more than NSAIDs. — 27 RCTs, 3101 women with dysmenorrhoea; chamomile vs NSAIDs one RCT, 160 women (n = 160) Evidence B source
  Pain MD -1.42 points (95% CI -1.69 to -1.15), one RCT, very low to low quality
• A 2024 meta-analysis of chamomile trials found a 1.88-point drop on the 21-point Pittsburgh sleep quality score across 5 studies, with very high heterogeneity. — Healthy or diseased adults in 10 clinical trials of chamomile, 772 participants (n = 772) Evidence A source
  PSQI WMD -1.88 (95% CI -3.46 to -0.31), I2 88.4%, 5 studies
• A 2019 meta-analysis found chamomile improved sleep quality by a moderate standardized amount. — Adults in 12 RCTs of chamomile for anxiety, insomnia or sleep quality (n = 12 RCTs) Evidence A source
  Sleep quality SMD -0.73 (95% CI -1.23 to -0.23)
• In a randomized trial of 80 Taiwanese postnatal women with poor sleep, two weeks of chamomile tea eased sleep problems, but the gain was gone 4 weeks later. — Postnatal women with poor sleep quality (PSQS 16 or more), Taiwan (n = 80) Evidence B source
  Positive effects limited to the immediate term; scores similar in both groups at 4-week post-test
• In a placebo-controlled pilot of 34 adults with chronic insomnia, 270 mg of chamomile extract twice daily for 28 days did not improve sleep diary measures. — Adults aged 18 to 65 with DSM-IV primary insomnia for 6 months or more (n = 34) Evidence B source
  No significant between-group differences in total sleep time, latency, efficiency, WASO or awakenings; no difference in adverse events
• In a single-blind trial of 60 nursing-home residents aged 60 and over, 200 mg chamomile extract capsules twice daily for 28 days improved sleep quality over placebo. — Elderly people aged 60 or more in a day care nursing home, Iran (n = 60) Evidence B source
  PSQI sleep quality better in treatment group after intervention (P < 0.05); baseline equal (P = 0.639)

Safety, limits and interactions

• People with contact allergy to daisy-family sesquiterpene lactones who swallowed capsules of freeze-dried German chamomile showed no flare of healed patch test reactions. — individuals with and without contact allergy to sesquiterpene lactone mix (n = not stated in abstract) Evidence C source
  No flare-up of healed patch tests; eczema worsening equal with chamomile and lactose
• A systematic review of 149 articles on warfarin lists chamomile tea among foods and herbs that raise bleeding risk with the drug. — 149 articles, 78 herbs, foods or supplements with warfarin (n = 149 articles) Evidence C source
  Chamomile tea named among bleeding-risk items; no size
• According to NIH, chamomile is likely safe in the amounts found in teas and other foods. — general population (n = -) Evidence E source
  No number
• According to NIH, interactions of chamomile with warfarin and some liver-metabolized drugs have been reported, and sedatives may also interact. — people taking warfarin, liver-metabolized drugs or sedatives (n = -) Evidence E source
  No number

What people believe that the data does not support

• An international psychiatry taskforce did not currently recommend chamomile for generalized anxiety disorder after weighing meta-analyses of trials. — WFSBP and CANMAT taskforce, 31 experts from 15 countries (n = -) Evidence A source
  Chamomile rated +/- (not currently recommended) for GAD
• According to NIH, there is very little information on whether chamomile helps insomnia. — People with insomnia Evidence E source
  Agency summary: very little information on insomnia

Who this works differently for

• In 176 colicky infants, a chamomile, lemon balm and heat-killed lactobacillus product cut daily crying by 44 minutes more than simethicone over 28 days. — 176 infants with colic (Rome III), 28 days (n = 176) Evidence B source
  Crying time -44 min/day vs simethicone (95% CI -58 to -30); responders 95% vs 68.4%
• Among 700 Italian women interviewed after childbirth, chamomile was one of the three herbs used most often in pregnancy, alongside almond oil and fennel. — 700 women, three hospitals in northern Italy (n = 700) Evidence C source
  189 regular daily herb users; no outcome reported for chamomile

What is still unknown

• The same 2024 review found no adverse events reported in any study, but all studies except one only waited for complaints instead of asking about side effects. — Adults in 10 clinical trials of chamomile, 772 participants (n = 772) Evidence A source
  No adverse events reported in any study; passive surveillance in all but one

The bottom line

On iron the two studies disagree. In adults eating a bread meal, a serving of camomile tea cut non-heme iron absorption by 47%, against 79 to 94% for black tea, and the abstract does not give the number of people. In 13 women, a chamomile infusion sweetened with panela made no significant difference to iron absorption from fortified bread. Each was a single test meal with a different bread and a different brew, so neither settles what an ordinary cup does. In 176 colicky infants, a commercial mixture of chamomile, lemon balm and heat-killed lactobacillus cut daily crying by 44 minutes more than simethicone over 28 days, in an open-label trial of an industry product. We found no trial of chamomile tea in infants. Who should be careful. NIH calls chamomile likely safe in the amounts found in teas. It also reports interactions with warfarin and with some drugs processed by the liver, and says sedatives may interact for theoretical reasons. A systematic review of 149 articles on warfarin lists chamomile tea among the items that raise bleeding risk, on case-report evidence with no size given. People with contact allergy to daisy-family sesquiterpene lactones who swallowed freeze-dried German chamomile in capsules had no flare of healed patch tests, and anaphylaxis was not studied. That tested skin flares only, so it does not show chamomile is safe for people allergic to daisy-family plants. Chamomile was among the three herbs used most often in pregnancy by 700 Italian women surveyed after childbirth, and that survey reported no outcomes for it. We found no data on its safety in pregnancy.

Sources

1. chte-r4-01 · USDA FNDDS 2021-2023, dataset
   Tea, hot, chamomile (FNDDS 92306700, FDC 2710505): energy 1 kcal per 100 g; 1 cup = 240 g: 2.4 kcal; 1 small = 360 g; 1 medium = 480 g; 1 large = 600 g
   USDA FNDDS 2021-2023, food code 92306700, FDC 2710505 · checked 2026-10-01
2. chte-r4-02 · clinical trial
   Inhibition by black tea was 79-94%, peppermint tea 84%, pennyroyal 73%, cocoa 71%, vervain 59%, lime flower 52% and camomile 47%.
   Br J Nutr, 1999 · checked 2026-10-01
3. chte-r4-03 · RCT
   Iron absorption of bread given alone or with chamomile infusion sweetened with panela (8%) was not significantly different.
   Nutrition, 2007 · checked 2026-10-01
4. chte-r4-04 · Cochrane review
   There was very limited evidence that chamomile was more effective than NSAIDs (MD -1.42 points, 95% CI -1.69 to -1.15; one RCT, 160 women).
   Cochrane Database Syst Rev, 2016 · checked 2026-10-01
5. ev-chsl-01 · meta-analysis of clinical trials
   A significant reduction in PSQI score (WMD: -1.88, 95 %CI: -3.46, -0.31, I2: 88.4 %, n = 5) was found.
   Complementary Therapies in Medicine, 2024 · checked 2026-10-06
6. ev-chsl-03 · meta-analysis of RCTs
   Noteworthy, our meta-analysis showed a significant improvement in sleep quality after chamomile administration (standardized mean difference = -0.73, 95% CI [-1.23, -0.23], P < 0.005).
   Phytotherapy Research, 2019 · checked 2026-10-06
7. ev-chsl-04 · RCT
   However, the scores for all three instruments were similar for both groups at 4-week post-test, suggesting that the positive effects of chamomile tea were limited to the immediate term.
   Journal of Advanced Nursing, 2016 · checked 2026-10-06
8. ev-chsl-05 · RCT
   There were no significant differences between groups in changes in sleep diary measures, including total sleep time (TST), sleep efficiency, sleep latency, wake after sleep onset (WASO), sleep quality, and number of awakenings.
   BMC Complementary and Alternative Medicine, 2011 · checked 2026-10-06
9. ev-chsl-06 · RCT
   However, after the intervention, sleep quality in the treatment group was significantly better than the control group (P<0.05).
   Complementary Therapies in Medicine, 2017 · checked 2026-10-06
10. chte-r4-07 · provocation study
    None of the subjects had a flare-up of healed patch test reactions. According to the NRS, SLM-positive individuals experienced a significant worsening of hand eczema, independently of whether they received chamomile or lactose capsules.
    Contact Dermatitis, 2020 · checked 2026-10-01
11. chte-r4-08 · systematic review
    While most food, herbs and supplements can be safely taken in moderation, healthcare professionals should be aware of the increased risk of bleeding when taking several food and herbs. These include Chinese wolfberry, chamomile tea, cannabis, cranberry, chitosan, green tea, Ginkgo biloba, ginger, spinach, St. John's Wort, sushi and smoking tobacco.
    Br J Clin Pharmacol, 2021 · checked 2026-10-01
12. chte-r4-10 · NIH agency page
    Chamomile is likely safe when used orally in amounts commonly found in teas and other foods.
    NIH National Center for Complementary and Integrative Health, Chamomile: Usefulness and Safety, updated November 2024 · checked 2026-10-01
13. chte-r4-11 · NIH agency page
    Interactions between chamomile and some drugs metabolized by the liver and warfarin (a blood thinner) have been reported, and there are theoretical reasons to suspect that chamomile might interact with other drugs as well, such as sedatives.
    NIH National Center for Complementary and Integrative Health, Chamomile: Usefulness and Safety, updated November 2024 · checked 2026-10-01
14. chte-r4-05 · guideline from meta-reviews
    Ashwagandha (++), galphimia (+), and lavender (++) were modestly supported in the treatment of anxiety disorders, while kava (-) and chamomile (+/-) were not recommended for generalised anxiety disorder.
    World J Biol Psychiatry, 2022 · checked 2026-10-01
15. ev-chsl-07 · NIH agency page
    There's very little information on chamomile's effect on insomnia.
    NIH National Center for Complementary and Integrative Health, Chamomile: Usefulness and Safety · checked 2026-10-06
16. chte-r4-06 · RCT
    Mean daily crying time at day 28 was significantly lower in group A (-44, 95% CI: -58 to -30, P<.001) and group B (-35, 95% CI: -49 to -20, P<.001) when compared to group C.
    Neurogastroenterol Motil, 2017 · checked 2026-10-01
17. chte-r4-09 · retrospective cohort
    Almond oil, chamomile and fennel were the most commonly used herbs.
    Hum Reprod, 2012 · checked 2026-10-01
18. ev-chsl-02 · meta-analysis of clinical trials
    No adverse events were reported in any of the studies although passive surveillance was used to assess adverse effects except in one study.
    Complementary Therapies in Medicine, 2024 · checked 2026-10-06