Lemon Balm

Lemon balm (Melissa officinalis) has plausible, well-studied anxiolytic, sleep-improving and mild antidepressant actions (mechanisms: GABAergic, cholinergic, antioxidant/rosmarinic-acid effects), and several randomized trials show benefit for anxiety, sleep and depressive symptoms — but there are no high-quality clinical trials specifically proving efficacy for Seasonal Affective Disorder (SAD). So it’s potentially helpful as an adjunct for winter-related low mood (because SAD commonly involves sleep disturbance, anxiety and low mood), but it should not replace first-line SAD treatments (light therapy, CBT, antidepressants) without medical advice.

Acts on brain neurotransmitter systems implicated in mood and anxiety: preclinical and human work suggests lemon balm and its constituents (rosmarinic acid, citrals, other phenolics/essential oils) modulate the GABAergic system (calming), have cholinergic activity (cognitive effects) and influence serotonergic pathways — all of which plausibly reduce anxiety, improve sleep and lift low mood. MDPI

Antioxidant / anti-inflammatory actions (rosmarinic acid etc.) provide additional neuroprotective and mood-relevant effects seen in several reviews. CentAUR

Clinical signal for mood, anxiety and sleep: randomized trials and systematic reviews report improvements in anxiety, sleep quality and depressive symptom scores in various populations after oral lemon-balm preparations. These symptomatic effects are the reason herbalists/clinicians consider it useful for winter “blues” or SAD-like symptoms. (But again: direct SAD trials are lacking.) BioMed Central

Forms people use

• Herbal tea (infusion), powdered leaf, liquid extracts/tinctures, standardized capsules or tablets, and essential-oil products (less for systemic mood effects). The EMA herbal monograph describes the standard pharmaceutical forms used in Europe. European Medicines Agency (EMA)

Usual dosages from regulatory guidance & clinical trials

• Herbal tea (infusion): EMA guidance for therapeutic use: 1.5–4.5 g of comminuted herb in 150 ml boiling water, 1–3 times daily (so roughly 1.5–13.5 g/day of dried leaf depending on frequency). Use as a soothing nightly or daytime tea per that schedule. European Medicines Agency (EMA)
• Powdered leaf: EMA: 0.19–0.55 g, 2–3 times daily (per finished product guidance). European Medicines Agency (EMA)
• Liquid extract / tincture: EMA: liquid extract 2–4 ml, 1–3 times daily; tincture 2–6 ml, 1–3 times daily (ethanol extracts described). European Medicines Agency (EMA)
• Capsule/extract doses used in trials (examples):
• ~300 mg nightly lemon balm extract (trial for sleep/mood outcomes — clinical trial protocols testing 300 mg/day). ICHGCP
• 500 mg three times daily (1.5 g/day) dried leaf powder for anxiety/sleep in a surgical in-patient trial (500 mg TID). ScienceDirect
• 600 mg/day and 700 mg/day hydroalcoholic extract have been used in pilot/clinical trials that reported benefits in sleep/depression measures. (Examples: pilot sleep/cognition trials; BMC randomized trial used 700 mg/day for depression in diabetics.) Europe PMC

How patients commonly take it for mood / winter low mood

• A practical, conservative starting approach (used in some studies / monographs): lemon-balm tea 1–3 times daily, or a standardized extract 300–600 mg/day (start low, e.g., 300 mg in the evening or 300 mg twice daily), and monitor effects for ~2–4 weeks. If using a tincture, follow the manufacturer’s label or EMA posology ranges. If symptoms persist beyond 2 weeks or worsen, consult a clinician (EMA recommends medical review if symptoms persist >2 weeks). European Medicines Agency (EMA)

Important practical notes

• Use standardized products when possible (so active constituent amounts are consistent).
• Combine with first-line SAD treatments where indicated (e.g., bright-light therapy) rather than replacing them. NHS guidance lists light therapy, CBT and antidepressants as many patients’ first-line options for SAD. nhs.uk

Systematic reviews / major reviews

• Nutrients (2024) — “Clinical efficacy and tolerability of lemon balm”: recent comprehensive review summarizing pharmacology (GABAergic, cholinergic) and human trials showing anxiolytic, sedative, sleep and mood benefits; notes need for more high-quality RCTs. MDPI
• Epistemonikos / systematic review of RCTs for depression/anxiety (search of trials up to Oct 2020) — meta-analytic approach assessing clinical trials of lemon balm for depression/anxiety. (Helpful summary of trial heterogeneity and outcomes.) Epistemonikos

Representative randomized clinical trials

• BMC Complementary Medicine (2023) — Randomized, double-blind, placebo-controlled trial in adults with type-2 diabetes and depressive symptoms: 700 mg/day hydroalcoholic extract vs placebo for 12 weeks — reported reductions in depression/anxiety scores in the lemon balm group. (Population: diabetic patients with depressive symptoms.) BioMed Central
• Pilot / crossover cognitive/mood trials (Newcastle, et al.) — acute doses of standardized lemon-balm extracts produced dose-dependent increases in calmness and improved some sleep/mood measures; shows a measurable human psychotropic effect. Northumbria University Research Portal
• Sleep/anxiety in CABG patients (double-blind RCT) — 500 mg TID dried leaf powder improved anxiety/sleep quality in hospitalized cardiac surgery patients (sample size moderate). ScienceDirect
• Pilot sleep trials (~600 mg/day) and other small RCTs showed improved sleep parameters and reductions in subjective anxiety. Europe PMC

Toxicology / safety evaluations

• Toxicological safety evaluation (2024) looked at toxicology of aqueous lemon-balm extracts and discussed safety data gaps and EMA safety statements (sedation risk, lack of reproductive toxicology). ScienceDirect