--- title: "Retinaldehyde" description: "Retinaldehyde is a vitamin A retinoid that skin can convert to retinoic acid. Results from tested creams cannot be assumed for every retinal product." --- # Retinaldehyde > Retinaldehyde is a vitamin A retinoid that skin can convert to retinoic acid. Results from tested creams cannot be assumed for every retinal product. Source: https://cosmetic-labs.com/glossary/retinaldehyde Created: 2026-11-09T13:59:14+00:00 Modified: 2026-11-09T13:59:14+00:00 Author: Emilie SCHOL ## Definition of Retinaldehyde Retinaldehyde, also called retinal, is a vitamin A-derived retinoid used in topical skincare. Skin cells can metabolize it into retinoic acid, but a retinaldehyde cream is not identical to prescription retinoic acid. ### Learn more ## Where retinaldehyde fits Retinaldehyde is a natural precursor in vitamin A metabolism. In experimental human skin-cell systems it can be converted into retinoic acid, a biologically active metabolite. It can also be directed toward retinyl esters, which are storage forms. The route through metabolism is more informative than saying retinal is simply the same substance as retinoic acid. The presence of a conversion pathway does not tell you how much active metabolite forms in every user's skin. Dose, vehicle and the skin model matter. Results in mouse skin or cultured cells support a mechanism, not an exact prediction of visible human results or a claim that one cosmetic concentration equals a prescription treatment. ## What has been observed in people? A randomized double-blind trial compared two specific retinaldehyde creams, 0.05% and 0.1%, over three months in 40 female volunteers. Both groups showed improvements in measured texture and hydration, with reductions in measured TEWL. The higher concentration alone showed a significant improvement in the melanin index in that trial. Those outcomes concern the two tested creams and the enrolled group, not retinaldehyde as a guaranteed stand-alone ingredient. The trial did not find a statistically significant difference between groups for its other reported measures. That is not proof that both concentrations are equivalent in every respect or that an unrelated product gives the same result. ## What about tolerance? The two tested creams were reported as well tolerated. This does not mean retinaldehyde can never sting, dry or irritate skin. A person beginning a retinoid routine may need to judge comfort against the entire formulation and the way it is used. Product instructions and individual response matter more than a blanket claim that retinal is always gentle. Avoid stacking the results of different retinoids as if they came from head-to-head trials. [Retinol](https://cosmetic-labs.com/glossary/retinol), retinaldehyde and retinoic acid have related chemistry, but their different conversion steps and formulations make an unqualified ranking of clinical strength misleading. A specific comparative claim needs a study that actually tests the products and endpoints being compared. ## How to read claims on a label Look for the exact named ingredient and the product's stated concentration if available. The number alone cannot establish shelf stability, delivery to skin or results after a given period. A sunscreen or moisturizer used alongside a retinal product also changes the overall routine, so the ingredient should not be credited for every visible change. Photoaging and pigmentation claims should be kept to what was measured. Improvement in a melanin index in one group is not evidence that retinaldehyde treats every pigment disorder. Persistent or changing lesions need medical evaluation rather than an anti-aging cosmetic. The clearest expectation is conditional: a properly formulated and tolerated product may improve some appearance measures with sustained use, but response is not guaranteed. Sources ## Sources and references References supporting this page are listed below. Source access dates and supported claims are recorded in the evidence notes where available. [Metabolism of topical retinaldehyde](https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:10473954&format=json&resultType=core) URL [https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:10473954&format=json&resultType=core](https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:10473954&format=json&resultType=core) [Metabolism of topical retinaldehyde](https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:10473954&format=json&resultType=core) URL [https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:10473954&format=json&resultType=core](https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:10473954&format=json&resultType=core) [Efficacy and safety of retinaldehyde 0.1% and 0.05% creams used to treat photoaged skin](https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:29663701&format=json&resultType=core) URL [https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:29663701&format=json&resultType=core](https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:29663701&format=json&resultType=core) [Efficacy and safety of retinaldehyde 0.1% and 0.05% creams used to treat photoaged skin](https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:29663701&format=json&resultType=core) URL [https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:29663701&format=json&resultType=core](https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:29663701&format=json&resultType=core) [Efficacy and safety of retinaldehyde 0.1% and 0.05% creams used to treat photoaged skin](https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:29663701&format=json&resultType=core) URL [https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:29663701&format=json&resultType=core](https://www.ebi.ac.uk/europepmc/webservices/rest/search?query=EXT_ID:29663701&format=json&resultType=core) --- ## Site identity - Organization: Cosmetic Labs - Description: Cosmetic Labs is a directory and a platform to meet all your cosmetic product development needs. From sourcing raw material to finding the best CRO for your needs. - Website: https://cosmetic-labs.com