Dipeptide-15 (Glycylglycine)_Dosage, benefits & legal status
Also known as Glycylglycine, Glycyl Glycine, Gly-Gly, Diglycine, Glycine Dipeptide, グリシルグリシン, 二肽-15
Two glycines joined together, the smallest a peptide can be.
What is Dipeptide-15 (Glycylglycine)?
Plain language first. The technical label stays, but it never stands alone.Overview
Dipeptide-15 is glycylglycine, and glycylglycine is two glycines stuck together. Glycine is the simplest amino acid there is, the only one with nothing hanging off its backbone, so this is the smallest molecule that can legitimately be called a peptide at all: 132 daltons, against roughly 1,000 for a typical cosmetic peptide and 4,000 for a GLP-1 drug. It is a real, registered cosmetic ingredient and it does appear in products you can buy. Chemists have used the same molecule as a buffer on the bench for most of a century, and that is where almost all of the published work on it comes from. A September 2026 launch promoted it as half of a proprietary complex, pairing it with truffle-derived exosomes and describing it as 99% high-purity and low molecular weight. Low molecular weight is accurate and also unavoidable: there is no high molecular weight version of two glycines. What is missing is evidence. No controlled human study of this ingredient on its own, for firmness or elasticity or anything else, came up in the research for this page, and the clinical testing described for that launch measured absorption and hydration of the whole formula rather than anything attributable to the dipeptide.
Dipeptide-15 is the cosmetic ingredient name for glycylglycine, a dipeptide of two glycine residues, CAS 556-50-3, molecular formula C4H8N2O3, molecular weight 132.12. Its listed cosmetic functions are hair conditioning and skin conditioning. Glycine is the smallest of the twenty amino acids and the only one with no side chain, so glycylglycine is the simplest peptide that can be constructed. The same molecule has been a standard laboratory buffer and model peptide for decades. Chinese regulatory records list it as a permitted existing ingredient with reported leave-on use at 2% for the body and 2% for the eye area. No controlled human trial of isolated Dipeptide-15 against a skin endpoint turned up in the searches behind this page.
What it's used for
Used in leave-on and rinse-off cosmetics as a skin and hair conditioning agent, typically at low percentages, and marketed in anti-aging positioning for firmness and elasticity. Present in moisturizers, cleansers, primers and makeup. The same molecule is sold separately as a biochemical buffer.
How does Dipeptide-15 (Glycylglycine) work?
What it does in the body, and where.There is no established mechanism for this ingredient on skin, and the size of the molecule is the reason that matters.
- 01Glycine has no side chainA chain of two glycines has almost no surface for a receptor or an enzyme to recognize specifically. There is nothing distinctive for biology to grip.
- 02At 132 daltons it can cross the barrierThat is the opposite of the usual complaint about cosmetic peptides. Crossing is not the same as doing anything once across.
- 03Its listed function is conditioningIn cosmetic nomenclature that covers surface effects rather than a biological pathway, and it is the only function the ingredient is registered for.
- 04The collagen and elasticity story is supplier copyMarketing positioning rests on supplier description rather than on any controlled study of the isolated ingredient found here.
What else is it used for?
Each group carries its own evidence level.Approved means regulators have cleared it for that purpose. Investigational means it is in trials. Early research means it is being studied and is not established.
Identity, and it is not in doubt
Supplement or cosmetic- RegulatoryDIPEPTIDE-15 carries CAS 556-50-3, EC number 209-127-3 and CosIng identifier 89911, with molecular formula C4H8N2O3 and molecular weight 132.12. Its listed functions are hair conditioning and skin conditioning.
- RegulatoryChina's inventory of existing cosmetic ingredients records the entry at number 02390 and gives its Japanese ingredient name as glycylglycine written in katakana. Two nomenclature systems therefore name the same molecule, settling the identity without relying on supplier marketing copy.
- No dataOne record conflict, and it is trivial: nearly every source gives the EC number as 209-127-3, while one ingredient catalog prints 209-127-8. Only the check digit differs and the catalog is the outlier.
The evidence gap
none- No dataNo controlled human trial of isolated Dipeptide-15 against a skin endpoint was found in the searching behind this page. Supplier listings describe improvements in elasticity, firmness and collagen; none cites a study.
- Lab studyGlycylglycine itself is extremely well studied, as a buffer and as the textbook model for a peptide bond. That literature says nothing about what it does on skin.
How it reached consumers in 2026
Supplement or cosmetic- RegulatoryOn September 21, 2026 a vegan skincare brand launched a reformulated spray serum built around a proprietary complex it named Peptide Exosome, described as a truffle-derived nano-exosome system combined with 99% high-purity, low molecular weight Dipeptide-15. The product went on sale the same day through Amazon and TikTok Shop.
- No dataThe same announcement doubled the formula's active serum concentration from 5% to 10% and expanded its oil blend from four oils to fifteen, and reports clinical testing of absorption amount, speed and depth plus layered hydration and flakiness. None of those measures is attributed to the dipeptide.
- No dataThe brand's page for the predecessor product footnotes its claims to consumer studies of 20, 22 and 21 individuals. Consumer studies of that size measure what people report, not what the ingredient does.
Calling it low molecular weight as though that were a formulation achievement. It is two glycines; there is no other version of it. The second misreading is attributing a finished product's clinical results to this ingredient. In the September 2026 launch that put Dipeptide-15 in front of consumers, the clinical testing described covered absorption amount, speed and depth and improvements in layered hydration and flakiness, all for the whole formula, and that formula also contains 70% collagen water and fifteen plant oils. The earlier version of that product supported its claims with consumer studies of 20, 22 and 21 people. Nothing in either set of claims isolates the dipeptide.
The published record
Papers about Dipeptide-15 (Glycylglycine) · this compound only
Searched: Dipeptide-15, glycylglycine, diglycine, Gly-Gly.
Left out: glycylglycine (ALONE, without a skin or cosmetic qualifier. THE critical rejection. This molecule has been a standard laboratory buffer and the textbook model peptide bond for most of a century. An unqualified query returns thousands of papers on buffer chemistry, metal chelation, enzyme kinetics and peptide-bond physics, NONE of which is about skin, and any one of them could be mistaken for cosmetic evidence); dipeptide-2 (a different cosmetic dipeptide already on this site, Val-Trp, with its own angiotensin-converting enzyme story); acetyl dipeptide-1 cetyl ester (another cosmetic dipeptide on this site, and the nearest name collision); oleoyl dipeptide-15 (a DIFFERENT INCI ingredient, CAS 244608-20-6, the acylated derivative. Not this molecule and not on this site); glycine (the constituent amino acid, with an enormous literature in nutrition, neurotransmission and collagen); peptide exosome (the trade name of the proprietary complex it was launched in, which is marketing language and not an ingredient); exosome (the delivery claim attached to it in that launch, a large and separate cell biology literature); d'Alba (the brand that launched it to consumers, whose other claims rest on truffle extract and plant oils); Trufferol (that brand's other proprietary name, unrelated to any peptide).
10 papers tagged human · 2 not reviews or lab · 2 clinical trial publications
8 registered trials · 4 with posted results
Furthest stage reached: Published trials only, 2 clinical trial publications, no phased trial registered
Counted from Europe PMC indexing, not read by a person; a human tag can land on reviews, commentary or lab papers; clinical trial publications is the narrower count. A preprint and its journal version count once.
At a glance
Four things to know about Dipeptide-15 (Glycylglycine)
Evidence
Cosmetic
Category
Skin and cosmetic
Common vial
Varies
Half-life
Not a meaningful measure for a topical conditioning agent
How much, and do you cycle it?
The range, and whether you take breaks.Reported leave-on use at up to 2% of the finished product, as the product directs. Daily, as part of a routine No range
Cosmetic conditioning agents are used continuously. There is nothing to cycle and no tolerance mechanism described for this molecule.
Not a meaningful measure for a topical conditioning agentNo figure
No topical or systemic half-life is published, and none is relevant: the ingredient is used at low percentages in leave-on cosmetics, not dosed.
You can compare this against the whole library to see where it sits.
What does it cost?
Typical dose and cost, in plain numbers.Dipeptide-15 (Glycylglycine) is not injected in the forms covered here
It is taken on the skin, in a finished cosmetic. Chinese regulatory records report leave-on use at 2% for whole-body products and 2% for the eye area, and state that below those concentrations the ingredient is not expected to harm human health under normal and reasonably foreseeable use. Actual concentrations in branded products are not disclosed.
How do you store it?
Before mixing, and after.Room temperature, out of light. Cap it tight after each use.
Dipeptide-15 (Glycylglycine) ships as a cream, gel, or serum. Keep it at room temperature away from sun and heat unless the label says otherwise. Refrigerating an emulsion can split the texture. Watch for color, smell, or separation changes and stop using it if any appear.
What are the side effects and cautions?
Known cautions and warnings for this compound.Who should avoid it
- Treating it as an active with demonstrated firming or elasticity benefit that no study checked here supports
- Any injectable or oral use: this is a topical cosmetic ingredient and nothing on its record supports anything else
Stop and get help
- Redness, stinging or a rash after a new product, a reason to stop that product rather than to blame this ingredient specifically
Common effects
- Nothing reported that is attributable to this ingredient on its own
- Hydration and immediate cosmetic effects in products containing it are generally traceable to humectants and oils in the same formula
Where this page says nothing is established, that means nobody has studied it, not that a compound is safe.
Is Dipeptide-15 (Glycylglycine) approved?
And where the numbers on this page come from.Not as a medicine. Dipeptide-15 (Glycylglycine) is sold without a prescription as a cosmetic ingredient, which is a different thing from being approved as a drug.
- Approval statusCosmeticSold without a prescription as an ingredient in cosmetics, such as skincare and hair products. The FDA does not approve cosmetics before they are sold, and being easy to buy says nothing about whether it works.
- RouteOn the skin, in a finished cosmetic
- Checked11 November 2026
- DoseFrom the concentration range manufacturers formulate at. This is a product strength, not a dose set by a regulator or a trial.
- Vial sizeFrom what vendors typically list; not a recommendation.
- SourcesCosmetic ingredient record for DIPEPTIDE-15 with CosIng identifier 89911 and EC 209-127-3Cosmetic ingredient record for DIPEPTIDE-15, CAS 556-50-3, with listed INCI functionsChina inventory of existing cosmetic ingredients, entry 02390, with the Japanese ingredient name recorded as glycylglycineChinese cosmetic ingredient regulatory database entry for 二肽-15, updated October 1, 2026Brand announcement of the September 21, 2026 launch naming Dipeptide-15 in its Peptide Exosome complexBrand product page for the predecessor serum, footnoting consumer studies of 20, 22 and 21 individuals
What has happened recently
Listed in the cosmetic ingredient nomenclature as DIPEPTIDE-15, EC number 209-127-3 and CosIng identifier 89911, with hair conditioning and skin conditioning as its functions. Entry 02390 in China's inventory of existing cosmetic ingredients, where its standard Chinese name is given as 二肽-15 and, decisively for the identity question, its Japanese ingredient name is recorded as グリシルグリシン, simply glycylglycine. One minor conflict: most records give the EC number as 209-127-3 while a single ingredient catalog prints 209-127-8. The catalog is the outlier and the check digit is the only difference.
You can compare this against the whole library, or read how to check a seller.
What else is like Dipeptide-15 (Glycylglycine)?
Others in Skin and cosmetic, side by side.If you're weighing Dipeptide-15 (Glycylglycine), it's worth reading Dipeptide-2, Hexapeptide-10 (Serilesine), and Hexapeptide-11 in the same class.
Two glycines joined together, the smallest a peptide can be.
- Dose
- Reported leave-on use at up to 2% of the finished product
- How often
- As the product directs
A two-residue peptide carrying a claim nothing tested.
- Dose
- Eye gel or cream, per product
- How often
- Daily
A well-researched sequence, researched for something else entirely.
- Dose
- Set by the finished product
- How often
- As directed by the product
A yeast-derived cosmetic peptide for elasticity, with a thin evidence trail.
- Dose
- Serum, per product
- How often
- Daily
Guides for this compound
- mcg vs mg: The Peptide Dosing Mistake to Avoid
Your vial says mg and your protocol says mcg. Here is the conversion and how to check it.
- How to Read a Peptide COA
What the purity number does and does not tell you, and how to spot an edited report.
- How to Vet a Peptide Vendor
Independent COAs, HPLC purity, and the red flags that mean walk away.
Sources
- Cosmetic ingredient record for DIPEPTIDE-15 with CosIng identifier 89911 and EC 209-127-3
- Cosmetic ingredient record for DIPEPTIDE-15, CAS 556-50-3, with listed INCI functions
- China inventory of existing cosmetic ingredients, entry 02390, with the Japanese ingredient name recorded as glycylglycine
- Chinese cosmetic ingredient regulatory database entry for 二肽-15, updated October 1, 2026
- Brand announcement of the September 21, 2026 launch naming Dipeptide-15 in its Peptide Exosome complex
- Brand product page for the predecessor serum, footnoting consumer studies of 20, 22 and 21 individuals
Beyond these, 14 records are indexed for this compound. Browse the records