Sodium Hyaluronate
Sodium hyaluronate is rated Clear, and it is one of the uncommon pages here where the reassuring number is both real and attached to the correct material: Fulton's 1989 rabbit-ear table prints a row for "Sodium hyaluronate" at 0, the salt itself, not a fabrication and not a mislabelled neighbour — though a single rabbit-ear 0 is still weak evidence, which is why the confidence is Low.
Lightweight humectant; no comedogenic concern on record.
What it is
Hyaluronic acid is a large linear polysaccharide — a glycosaminoglycan built from repeating disaccharide units — that binds and holds water, which is why the cosmetics industry uses it as a humectant and skin-conditioning agent. Sodium hyaluronate is its sodium salt: the same polysaccharide backbone with sodium as the counter-ion, more stable and more soluble than the free acid. Backbone identity is not identity of material, though. Hyaluronic Acid and Sodium Hyaluronate are separate declared ingredients with separate INCI names, and this page is filed under the salt because the salt is the material the primary table tested. The score stays on the salt. The Cosmetic Ingredient Review's 2009 final safety assessment covers hyaluronic acid, sodium hyaluronate and potassium hyaluronate together. It reports that they function in cosmetics as skin conditioning agents at concentrations up to about 2%, and that the hyaluronic acid used in cosmetics is now obtained chiefly by bacterial fermentation (historically it was extracted from rooster combs). That is a safety document describing what the material is and how it is used; it is not a comedogenicity study, and this page does not use it as one.
Why we rate it Clear
We rate it Clear at Low confidence. The only exact-material result we identified in the primary inventories we hold is a rabbit-ear reading, and that is the whole reason the confidence is Low rather than higher. The legacy number, and this time it is the actual ingredient. James Fulton's 1989 survey in the Journal of the Society of Cosmetic Chemists is the source of nearly every comedogenic score in circulation, and we read its Table I off a render of the journal scan rather than a list quoting it. It prints a row for "Sodium hyaluronate" at a comedogenicity grade of 0 on his 0-to-5 scale. That row is the salt itself — it is not in Section VI, "Oils," so it does not inherit the asterisk that qualifies the oils and butters, and it carries no range or asterisk of its own. On this site that is the exception rather than the rule: most of the famous numbers turn out, on inspection, to belong to a different material than the one they are quoted against, or to trace to no measurement at all. Here the printed row and the ingredient are the same thing, and the printed number is 0. A 0 from this assay still deserves exactly as much scepticism as a 4 from it, and the rest of this site spends its time saying so. The rabbit ear is a contested, oversensitive model; Fulton called his own survey "not at all definitive." On his own published key, a grade of 0 to 1 "is not considered significant," so a 0 sits at the bottom of the band he treated as noise rather than finding. One reassuring rabbit-ear reading is thin evidence, and it is all the direct comedogenicity evidence we have for this ingredient — which is why the rating is Clear but the confidence is Low. The other primary inventories we hold are silent. Fulton's earlier 1984 rabbit-ear paper carries no hyaluronate row of any kind; Morris and Kwan's 1983 assay tested 32 materials — seven lanolins, nine vegetable oils, eleven esters and five surfactants — and none of them is a hyaluronate; and Nguyen, Dang and Maibach's 2007 survey tested esters and a short list of other materials, again with no hyaluronate. Those absences are verified in the tables themselves rather than assumed, and what they mean is that the 1989 row has nothing beside it to confirm or contradict it. The wider point is worth stating plainly, because it is where a reader arrives from. Hyaluronic acid is routinely described online as "non-comedogenic" and as an ingredient that "does not clog pores." Those assertions are common and largely unsourced. Where a traceable number does appear behind them, it is this Fulton 0. The rating is not built on the popularity of the claim; it is built on the one measurement we could trace, stated with its weakness.
What the evidence doesn’t tell you
We identified no human comedogenicity study of sodium hyaluronate or hyaluronic acid — no study, in the sources we hold, that applied it to skin and counted comedones as its endpoint. The rating therefore rests on a single legacy assay and nothing more direct. That assay is the Fulton rabbit-ear model: the ingredient diluted to roughly 10% in propylene glycol, applied to the inner ear of three New Zealand albino rabbits, five days a week for two weeks, follicular keratosis scored under a micrometer. It is the same model this site discounts when it condemns an oil, and consistency requires discounting it here too — a 0 from a weak model is weak evidence of a 0. The row being real and correctly attributed removes one common error; it does not turn one rabbit-ear reading into a strong result. A safety assessment is not a comedogenicity study. The CIR document cited here concludes the hyaluronates are safe as used and describes their function and typical concentration; it does not measure follicular plugging, and safety and comedogenicity are different questions. The free acid and the sodium salt share a backbone, but they are separate declared materials, and we have not treated a reading of one as a reading of the other — Fulton's printed row is the salt, and the salt is what this page rates. Hyaluronic acid itself has no row in anything we hold. What we cannot say is anything about how molecular weight, cross-linking or concentration might bear on the question, because no comedogenicity study we found varied any of them. Hyaluronic acid is also a water-soluble polysaccharide rather than a lipid, but we are not going to reason from that to a conclusion the evidence has not tested: an absence of a plausible mechanism is not a measurement. Finally, a rating is a property of an ingredient, not of a finished product. Hyaluronic acid is almost always formulated alongside other materials, and a serum or cream that pairs it with heavier, occlusive ingredients can still clog pores; the 0 here belongs to the humectant, and the behaviour of any particular product is a separate question this page does not answer.
Where you’ll see it
On a label it appears as Sodium Hyaluronate. Hyaluronic Acid is a separate declaration, and the number on this page belongs to the salt, not to it. Sodium hyaluronate is common in serums, essences, moisturisers, eye creams, sheet masks and hydrating toners, and it sits in the water phase of a formula. The CIR safety assessment reports the hyaluronates in use as skin conditioning agents at concentrations up to about 2%, so it is typically a small fraction of a formula despite the marketing weight it carries; its position on an ingredient list tells you little on its own.
Sources
Each source says what it actually is. Several widely-cited “sources” for comedogenic ratings are republishing the same 1989 assay, and counting them as independent agreement is how a thin evidence base gets made to look thick.
- Fulton JE. "Comedogenicity and irritancy of commonly used ingredients in skin care products." J Soc Cosmet Chem 40:321-333 (1989) The primary source of nearly every comedogenic number in circulation, read off a render of the journal scan rather than a list quoting it. Method: ingredient at roughly 10% in propylene glycol, inner ear of three New Zealand albino rabbits, five days a week for two weeks, follicular keratosis scored under a micrometer, on a 0-to-5 scale. Its Table I prints a row for "Sodium hyaluronate" at a comedogenicity grade of 0 — the salt itself, outside the asterisked "Oils" section, with no range or asterisk. Fulton's own key: 0 to 1 "not considered significant," and he called the survey "not at all definitive." Cited as the one traceable comedogenicity datum for this ingredient, and as the same contested rabbit-ear assay this site discounts elsewhere — a reassuring 0 from it is as weak as a condemning 4.
- Fulton JE, Pay SR, Fulton JE III. "Comedogenicity of current therapeutic products, cosmetics, and ingredients in the rabbit ear." J Am Acad Dermatol 10(1):96-105 (1984) Fulton's earlier rabbit-ear paper, on its own 0-5 scale. Cited for what it does NOT contain: no hyaluronate row of any kind. We hold its table in full, so the absence is verified rather than assumed, and it supports no rating of this ingredient in either direction.
- Morris WE, Kwan SC. "Use of the rabbit ear model in evaluating the comedogenic potential of cosmetic ingredients." J Soc Cosmet Chem 34:215-225 (1983) An independent primary rabbit-ear assay on the same 0-5 scale, six years before Fulton 1989 and willing to contradict him in print. Its 32 test materials are seven lanolins, nine vegetable oils, eleven esters and five surfactants, and no hyaluronate is among them. Cited for that verified absence, which is part of why the 1989 row stands with nothing beside it.
- Nguyen SH, Dang TP, Maibach HI. "Comedogenicity in rabbit: some cosmetic ingredients/vehicles." Cutan Ocul Toxicol 26(4):287-292 (2007) The only later rabbit-ear comedogenicity survey we could find, on a 0-4 scale, cited for what it does not contain: its test set is esters and a handful of other materials, with no hyaluronate. It is the last of the primary inventories we hold, and the last place a second reading of this material could have come from.
- Becker LC, Bergfeld WF, Belsito DV, Klaassen CD, Marks JG, Shank RC, Slaga TJ, Snyder PW; Cosmetic Ingredient Review Expert Panel. "Final Report of the Safety Assessment of Hyaluronic Acid, Potassium Hyaluronate, and Sodium Hyaluronate." Int J Toxicol 28(4 Suppl):5-67 (2009) A Cosmetic Ingredient Review expert-panel SAFETY assessment, in its final-report state, covering hyaluronic acid and its potassium and sodium salts together. Cited for what the material is and how it is used — a large glycosaminoglycan polysaccharide functioning as a skin conditioning agent at concentrations up to about 2%, obtained chiefly by bacterial fermentation. A safety review is not a comedogenicity study and we do not use it as one: it concludes the ingredients are safe as used and says nothing about follicular plugging. Safety and comedogenicity are different questions, and this document speaks to the first.
Others in the same family
Humectants behave similarly enough that the evidence for one is often wrongly read across to the others. These are its structural relatives, not a guess. What the evidence says about humectants as a family ›
Last reviewed 2026-08-12 · How we decide