PHA (lactobionic acid)

PHA · polyhydroxy acids · lactobionic acid · gluconolactone · acido lattobionico

Larger 'next-generation' exfoliating acids marketed as gentler alternatives to AHAs.

TipoCosmetic (topical)

Il voto risponde a: What does the human evidence support for: Gentle exfoliation & hydration?

Grado

Limitata

Il voto misura la qualità dell'evidenza, non è un consiglio ad assumere o acquistare.

Classe: Skincare / topical
Uso principale: Gentle exfoliation & hydration
Forza evidenza: low
Ultima revisione: 2026-07-01

In sintesi

The gentle cousins of AHAs: bigger molecules that exfoliate more mildly and add hydration and antioxidant character. Good for sensitive skin, but with a thinner evidence base than glycolic or lactic acid.

Cosa dice l'evidenza

Polyhydroxy acids (PHAs) such as gluconolactone and lactobionic acid are larger molecules than classic AHAs, so they penetrate more slowly and tend to be less irritating, while also acting as humectants and, for lactobionic acid, offering antioxidant/chelating properties. The evidence is more limited and often industry-linked compared with glycolic/lactic acid, and mostly points to good tolerability with milder exfoliation. This is cosmetic use, not a peel procedure, and product formulation decides the result. Grade C: a sensible gentle option, with modest independent data.

Studi chiave

[1]
Polyhydroxy acids in cosmetic use · review
Gentler exfoliation with humectant properties.
Apri su PubMed ↗
[2]
Lactobionic acid antioxidant / humectant properties · review
Extra hydration and antioxidant character.
Apri su PubMed ↗
[3]
PHA tolerability vs AHA · review
Milder profile suits sensitive skin.
Apri su PubMed ↗

Vedi tutti gli studi su PubMed ↗

Meccanismo

Exfoliate by loosening surface corneocyte bonds like AHAs but more slowly due to larger molecular size; also bind water (humectant) and, for lactobionic acid, chelate metals and scavenge some free radicals.

Sicurezza

Better tolerated than stronger AHAs, so often chosen for sensitive or reactive skin; still increase the value of daily sun protection. Irritation is less common but possible.

Contesto dosaggio

Used across a range of concentrations in leave-on and rinse-off products; the appeal is tolerability rather than a high, aggressive percentage. Formulation and pairing matter more than the number.

Esempi di applicazione

Chosen as a gentler exfoliant for sensitive or reactive skin.
Used more often than strong AHAs thanks to milder action.
Still paired with daily sunscreen.

Nota dal campo

PHAs are the 'sensitive-skin' answer to acids — gentler and hydrating, but with less independent evidence than glycolic or lactic acid. We grade lactobionic/PHAs C and treat them as tolerability picks, not upgrades.

Molecole correlate

AHA (glycolic / lactic acid)B Panthenol (provitamin B5)C NiacinamideB

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