Glycine

Of 1,579 on-market glycine products in the January 2026 DSLD dump, the median declared dose is 250 mg, and 100.0% list Glycine (unmodified free amino acid) as the primary form.

Form share

Of 1,573 products with an identifiable primary form, here is the share held by each form of Glycine on the market today.

Form share over time

Entry-year breakdown of the top forms, 2012–2025.

Dose distribution

Deciles of declared dose per serving (mg), among 1,038 products with a disclosed amount.

• 71.4% of products fall below the fairy-dust threshold (600 mg, 20% of the studied low dose).
• 33.2% of products don't disclose an amount because Glycine is declared inside a proprietary blend.

Top brands

Forms explained

Reference values

• RDA (adult): not established — Non-essential/conditionally-essential amino acid; no IOM/NASEM RDA exists for individual non-essential amino acids (Elango R et al. 2023, PMC10334138).
• Tolerable Upper Intake Level (adult): not established — Not established -- no IOM/EFSA/FDA UL exists for glycine specifically.
• Studied clinical dose range: 3000–3000 mg
• Kawai N et al. 2012, Front Neurol 3:61, PMID 22529837 -- 3g oral glycine before bed under a sleep-restriction protocol improved subjective sleep quality, reduced next-day fatigue, and improved daytime cognitive performance vs placebo. [Study authors were employees of Ajinomoto, a major amino-acid manufacturer -- conflict-of- interest caveat worth carrying alongside this citation.]
• Note: Trimethylglycine (betaine/TMG) and Dimethylglycine (DMG), though sometimes marketed alongside glycine, are chemically and functionally DISTINCT compounds (methyl-donor/ osmolyte biology vs. glycine's neurotransmitter/collagen-precursor biology) -- modeled as separate compounds in this reference set, not as forms of glycine.