Lemon balm
Summary
Lemon balm is a mint-family herb traditionally used for calm and sleep. A meta-analysis of small trials found lower anxiety and depression scores than placebo, with high heterogeneity between studies. Single-dose lab studies showed more calmness under stress at 600 mg. No serious side effects were reported, but trials are few and short.
Key facts
- The leaf of Melissa officinalis, a mint-family herb containing rosmarinic acid, citral and other compounds[4]
- Pooled trials: anxiety (SMD −0.98) and depression (SMD −0.47) scores lower than placebo, with high heterogeneity[1]
- In a crossover lab study, 600 mg increased calmness during a stress test[2]
- 7 RCTs: small falls in total cholesterol and systolic pressure; high risk of bias in many studies[3]
- 1 graded human outcome on this page
- October 11, 2026
How it works
ProposedAnimal and cell studies suggest lemon balm compounds act on GABA, cholinergic and serotonin signalling; this has not been confirmed in humans.[4]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Mood during a laboratory stressor | Improved | Grade D | Crossover RCT · n = 18 · 2004 Healthy young adults Form: Standardized lemon balm extract · Dose: Single doses of 300 mg and 600 mg · Duration: Single doses, 7-day washout 600 mg reduced the negative mood effects of a 20-minute stress battery, with higher calmness and lower alertness ratings; 300 mg sped up maths processing without loss of accuracy. | 15272110 (opens PubMed)Source [2] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Lemon balm leaf extract | Varies | No head-to-head human absorption data in the sources cited here. | No serious side effects reported in pooled trials.[1] | Anxiety, mood, stress and cardiometabolic trials |
Studied doses
Doses studied in human trials ranged from 300 mg to 600 mg of standardized extract as single doses in laboratory studies; longer trials in the pooled analyses used varied products and doses.[2][1]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
None found in our sources.
Who should be careful
- Pregnancy and breastfeeding
- Not studied in the trials cited here.[1]
- Before driving or tasks needing alertness
- A 600 mg dose lowered self-rated alertness in a lab study.[2]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
Frequently asked questions
Does lemon balm help anxiety?
A meta-analysis of small trials found lower anxiety scores than placebo, but studies varied a lot, so results are uncertain.[1]
Does lemon balm make you sleepy?
In a lab study, 600 mg increased calmness and lowered alertness ratings.[2]
Is lemon balm safe?
No serious side effects were reported in the pooled trials, which were small and short.[1][3]
Does lemon balm lower cholesterol?
A meta-analysis of 7 trials found a small fall in total cholesterol, with high risk of bias in many studies.[3]
Sources
- [1]The effects of lemon balm (Melissa officinalis L.) on depression and anxiety in clinical trials: A systematic review and meta-analysis. Phytother Res, 2021. meta-analysis
- [2]Attenuation of laboratory-induced stress in humans after acute administration of Melissa officinalis (Lemon Balm). Psychosom Med, 2004. crossover-RCT
- [3]Effects of Melissa officinalis (Lemon Balm) on cardio-metabolic outcomes: A systematic review and meta-analysis. Phytother Res, 2020. meta-analysis
- [4]Clinical Efficacy and Tolerability of Lemon Balm (Melissa officinalis L.) in Psychological Well-Being: A Review. Nutrients, 2024. review
What changed
- New monograph: definition, key facts, evidence table, studied doses, safety and FAQ written from the cited abstracts and fact sheets.