Ingredient glossary

Retinal

What Retinal does for your skin, who it suits, and what to watch for.

INCI: Retinaldehyde

Solid and proven

In short: Retinal delivers anti-aging support and texture, suits most skin types, and the evidence behind it is moderate. One thing to know: not for pregnancy or breastfeeding; introduce it gently.

What it does
Anti aging, texture
Best for
Most skin types
Watch out
Not for pregnancy or breastfeeding; introduce it gently
Evidence
Moderate
How long
3 months+
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The molecule

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The Glow take

One of the ingredients I trust most.

When your goal is softening fine lines and keeping skin firm, Retinal delivers, with a solid amount of evidence behind it. Skip it while you are pregnant or breastfeeding, and the rest of the time bring it in slowly.

— Maya

What it does

  • anti aging
  • texture
  • brightening

Retinal scores -1 on barrier support. It is one of only 8 ingredients in our glossary that go below zero there. A negative score means it asks something of the barrier rather than giving something back, which is why it needs introducing slowly and pairing with ingredients that do support the barrier. It is not a reason to avoid it: the same evidence that shows the irritation also shows the long-term gains. See where it sits against all 291 of them →

moderate evidenceThe one vehicle-controlled trial tested 0.05% for 44 weeks in 125 people and cut measured wrinkle depth and roughness where the vehicle changed nothing. The water-loss, hydration and pigment figures come from a separate 40-person trial with no placebo arm, so they are before-and-after readings on people using a cream: texture, TEWL and hydration improved on both 0.05% and 0.1% with no significant difference between them, and a 6.5% drop in melanin index reached significance only in the 0.1% group. Most of this work was run or funded by companies selling retinaldehyde.

On a label: works best above 0.05%.

Who it's for, and who should skip it

Tends to suit

  • normal
  • oily
  • combo

Approach with care

  • pregnancy
  • breastfeeding
  • very sensitive
  • compromised barrier
  • Clogs poresLow
  • Irritation riskModerate

How it fits each skin type

  • DrySuits
  • CombinationSuits
  • OilySuits
  • SensitiveTake care

Take extra care if any of these apply to you: pregnancy, breastfeeding, compromised barrier.

Where it fits in your routine

WhenEvening
Where in the orderAfter cleansing, before your moisturizer

Nobody has measured whether Retinal changes how your skin handles sun.

No human study has measured minimal erythema dose, UV-induced erythema, sunburn cell formation or UV-induced DNA damage in skin treated with cosmetic retinol or retinaldehyde, so we do not know whether either changes how skin responds to UV; the SCCS opinion on Vitamin A (SCCS/1576/16, reaffirmed in the October 2022 revision SCCS/1639/21) names retinol and retinal and records no clinical reports of phototoxic or photosensitising effects, and when the EU restricted retinol in Commission Regulation (EU) 2024/996 it required only a vitamin A intake warning and no sun warning, but neither is a measurement of sun sensitivity.

SCCS Opinion on Vitamin A SCCS/1576/16 (6 October 2016) and its revision SCCS/1639/21 (adopted 24-25 October 2022), section on human data and phototoxicity/photosensitisation; Commission Regulation (EU) 2024/996 of 3 April 2024, Annex III entry 376; CIR Expert Panel re-review book for Retinol and Retinyl Palmitate (September 2012) and the reopened draft report (June 2013); Health Canada Cosmetic Ingredient Hotlist entries for Retinal and for Retinol and its esters; Antille and colleagues, Journal of Investigative Dermatology 2003 (retinyl palmitate human UVB challenge); Sorg and colleagues, Photochemistry and Photobiology 2005 (hairless mice); Smit and colleagues, Acta Dermato-Venereologica 2000 and Slade and colleagues, Photodermatology Photoimmunology and Photomedicine 2009 (retinoic acid). Three independent searches of PubMed via E-utilities, Europe PMC full text and ClinicalTrials.gov located no human study of either endpoint for cosmetic retinol or retinaldehyde, in either direction.

Give it three months or more — that is when the change first became measurable.

What was measured, and in whom

Measured on: crow's-feet wrinkle depth and surface roughness, silicone-replica optical profilometry, versus vehicle.

The only vehicle-controlled trial is Creidi et al. 1998: 125 patients on 0.05% retinaldehyde, 0.05% retinoic acid or the retinaldehyde vehicle, with a silicone replica of the left crow's feet taken at baseline, week 18 and week 44 and read by optical profilometry. Wrinkle and roughness features were significantly reduced with retinaldehyde at week 18; at week 44 the reduction was less pronounced, and the vehicle produced no significant change at any assessment point. The result therefore dates to week 18, not to the end of the study, and it does not keep growing with time on treatment. Because there is no assessment between baseline and week 18, the true onset could be earlier and simply was not looked for. The other retinaldehyde trials cannot date onset at all: the 40-woman 3-month study and the 56-woman 24-week study both compare 0.1% against 0.05% with no vehicle arm, which is where the often-quoted TEWL, hydration and 6.5% melanin-index figures come from. Most of this work was run or funded by companies selling retinaldehyde; 0.05% is consumer strength.

Creidi et al., J Am Acad Dermatol 1998;39(6):960-5, 'Profilometric evaluation of photodamage after topical retinaldehyde and retinoic acid treatment', PMID:9843009 - abstract read: replicas at baseline, weeks 18 and 44; significant at week 18, less pronounced at week 44, vehicle unchanged throughout. Concentration comparisons without a vehicle arm, not used for timing: PMID:29663701, PMID:41729119.

Light, and how to keep it

Retinal breaks down in light. The packaging is doing real work: opaque, and closed between uses.

Family evidence: the vitamin A family photodecomposes under UV; the aldehyde inherits the family photochemistry and no study shows it as the stable exception.

PMID:17576350(abstract)

Plays well with

Retinal, answered

Is Retinal safe during pregnancy?

No. Retinal is best avoided during pregnancy and breastfeeding. If you are pregnant or trying, leave this one out and ask your doctor about a safe alternative.

Who should avoid Retinal?

Approach Retinal with care if any of these apply to you: pregnancy, breastfeeding, very sensitive, and compromised barrier. Its irritation risk is moderate, so introduce it slowly and patch test first.

What concentration of Retinal actually works?

Research tends to show Retinal starts pulling its weight above 0.05%. If a brand prints the percentage, that is the number to look for.

Does Retinal go off?

It breaks down in light, and that is the part that has been measured. Family evidence: the vitamin A family photodecomposes under UV; the aldehyde inherits the family photochemistry and no study shows it as the stable exception. So the packaging is not decoration: opaque, and closed between uses. Heat, air and simple age matter too, and we have not sourced numbers for those, so treat this as one reason a product weakens rather than as a shelf life.

During pregnancy

Leave Retinal out while you are pregnant or breastfeeding. It sits on the list of ingredients usually held back during this time.

When in doubt, check with your doctor or midwife. They outrank any website, including this one.When it is worth booking →

Commonly confused with

  • RetinolRetinal sits one conversion step closer to the active form than retinol, so it tends to work a little faster.

More skincare terms people mix up →

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Sources & how we reviewed this

  1. PMID 29663701abstract only, the full text is paywalled
  2. PMID 9843009abstract only, the full text is paywalled
  3. PMID 36220974read in full
  4. PMID 41729119read in full

Last reviewed August 2026. Educational information about a cosmetic ingredient, not medical advice.