Quick Comparison

GlycineLemon Balm
Half-Life1-2 hours (plasma)3-5 hours (rosmarinic acid)
Typical DosageFor sleep: 3 g taken 30-60 minutes before bed. For general nootropic use: 1-3 g daily. For NMDA co-agonism (with racetams): 1-3 g daily. Sweet taste, dissolves easily.Standard: 300-600 mg extract daily for anxiety/cognition. For sleep: 300-600 mg 30-60 minutes before bed. Cyracos is the most studied extract (standardized to rosmarinic acid). Tea: 2-4 cups daily. Can be combined with valerian for sleep.
AdministrationOral (powder, capsules). Sweet-tasting powder dissolves easily in water.Oral (capsules, tea, tincture). Cyracos extract is most studied. Pleasant lemon-mint taste in tea form.
Research Papers10 papers8 papers
Categories

Mechanism of Action

Glycine

Glycine acts as an inhibitory neurotransmitter by binding to strychnine-sensitive glycine receptors (GlyR) in the brainstem, spinal cord, and retina, hyperpolarizing neurons via chloride influx. It also serves as a mandatory co-agonist at the glycine-binding site (NR1 subunit) of NMDA glutamate receptors — without glycine binding, NMDA receptors cannot open their ion channel even when glutamate is present. This dual role means glycine both calms neural activity (sleep, anti-anxiety via GlyR) and supports excitatory learning processes (NMDA-dependent LTP and memory consolidation). Glycine lowers core body temperature at night by promoting peripheral vasodilation through nitric oxide, which improves sleep onset. It is a precursor for glutathione synthesis and modulates the glycinergic system in the suprachiasmatic nucleus.

Lemon Balm

Lemon balm inhibits GABA-transaminase (GABA-T), the enzyme that converts GABA to succinic semialdehyde in the GABA shunt, increasing GABA availability in synaptic terminals and producing anxiolytic effects via GABA-A (alpha2, alpha3 subunits) and GABA-B receptors. Rosmarinic acid provides antioxidant effects via Nrf2 activation and anti-inflammatory effects through COX-2 and NF-kB inhibition. Lemon balm inhibits acetylcholinesterase (AChE) at the catalytic site, mildly increasing acetylcholine in the hippocampus and cortex — explaining cognitive enhancement at moderate doses via muscarinic M1 and nicotinic receptor activation. At higher doses, GABAergic effects dominate, producing sedation useful for sleep. Additional mechanisms may include 5-HT2A antagonism and muscimol-like GABA-A modulation from trace constituents.

Risks & Safety

Glycine

Common

Essentially none at standard doses. Sweet taste makes it easy to take.

Serious

None documented. One of the safest supplements available.

Rare

Nausea, soft stools at very high doses (>10 g).

Lemon Balm

Common

Very well-tolerated. Mild drowsiness at higher doses.

Serious

May reduce thyroid hormone levels — caution with hypothyroidism.

Rare

Nausea, abdominal pain.

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