Dipeptide-2_Dosage, benefits & legal status

Two under-eye peptides sit on this site, sold for the same thing on the same enzyme rationale. Comparing them is the most useful thing this page can do, and the comparison goes in an unexpected direction.

1. 01
   The enzyme, and where the evidence comes from

   Angiotensin-converting enzyme raises blood pressure by producing a vasoconstrictor. Food chemists have known since the early 1990s that certain small peptides from food proteins inhibit it, and valyl-tryptophan is one of them. That work is real and it is oral: swallow the peptide, it is absorbed, it acts on circulating enzyme and blood pressure falls slightly. Every well-documented thing about this molecule comes from that tradition.
2. 02
   The claim that was built on it

   The cosmetic claim is different in kind: that inhibiting this enzyme in skin improves lymphatic drainage and so reduces the fluid that makes under-eye bags. There is no experiment at any level supporting that bridge. Not in cells, not ex vivo, not in people. The enzymology is genuine and the inference drawn from it is unsupported, and those two facts are easy to conflate because the first lends the second its vocabulary.
3. 03
   Why the human data cannot help

   The cited study is 20 women aged 40 to 60 applying 3% of the blend twice daily for 56 days, reported as the share of volunteers with reduced bag volume, 65% at 28 days and 70% at 56 days. No control group, no statistics and no stated measurement method. Even if it were well run, it tested three actives at once, so nothing in it belongs to this peptide. There is a further reason to doubt this one is the active component: hesperidin methyl chalcone is a flavonoid with its own long-standing use for vein tone, and palmitoyl tetrapeptide-7 carries a fatty chain that will cross skin far better than a bare dipeptide. Of the three, this is the component least likely to be responsible for anything the blend does.
4. 04
   The comparison with Eyeseryl, the interesting part

   Eyeseryl, also on this site, is sold for the same purpose on the same enzyme-inhibition rationale. The split between them is clean and counterintuitive: this peptide has the better-published enzymology and the worse cosmetic logic, because its documented action is oral and vascular rather than topical and lymphatic. Eyeseryl's version of the claim cites no study at all. So the better-documented molecule here is the one whose documentation points away from the use it is sold for.
5. 05
   The delivery question nobody has answered

   Both claims require a water-loving peptide applied to the skin to reach dermal lymphatics. No permeation data exists for this peptide. The only ingredient in the broader topical-peptide class with published permeability data is Argireline, and a 2025 review of it found 0.22% reaching the outer dead layer, 99.7% washed off and nothing reaching the receptor solution. A two-residue peptide is smaller and may behave differently, and nobody has measured it.