Licorice Root Extract vs Retinaldehyde

Licorice Root Extract: Some licorice-derived compounds are studied for uneven pigmentation. Retinaldehyde: Some formulas improve photoaged texture and pigmentation over months.

Research updated 2026-10-25

Five licorice root products on white, including two Acwell bottles, Éminence, Horbäach liquid extract and Versed

Four retinaldehyde products with two boxes on white, from Paula's Choice, Medik8, Naturium and Prequel

Which one?At a glance What it helps Diagrams Using both Strengths Results Safety How it works Products Questions

Which one is right for you?

Choose Licorice Root Extract if…

Consider as an optional pigment ingredient; independent clinical evidence is limited.

Mild uneven tone
Sensitive skin that dislikes stronger pigment actives
Modest expectations

Choose Retinaldehyde if…

Consider for photoaged texture; introduce slowly and judge the complete formula.

Fine lines and texture
Retinol isn’t enough
You can introduce it slowly

Fine together

Can you use both?

Licorice is soothing and can offset retinaldehyde redness.

At a glance

● Licorice Root Extract

● Retinaldehyde

Type

Botanical pigment-targeting mixture

Vitamin A precursor (retinal)

What it does

Some licorice-derived compounds are studied for uneven pigmentation.

Some formulas improve photoaged texture and pigmentation over months.

Best for

Melasma; Uneven Skin Tone

Wrinkles and Fine Lines; Uneven Skin Tone

Studied concentrations

Extracts are not standardized; the cited small study used a liquiritin cream.

0.05% and 0.1% creams in the cited three-month trial.

When to use

On the schedule specified for the product or prescribed treatment.

At night; introduce gradually according to the product label.

Time to results

Usually assessed over 8–16 weeks

Assess over roughly 3 months; photoaging can take longer

Irritation

Botanical extracts can cause allergy or stinging; check the complete formula.

Dryness, stinging and peeling can occur; avoid irritated areas.

Sensitive skin

Choose a simple formula and test a small area first. Avoid actively inflamed or broken skin unless the product is specifically directed for it.

Available

Prescription or cosmetic status depends on the active, formula and country; check the label.

What it helps

Compare uses by strength of evidence. Evidence level describes confidence in a benefit, not its size.

Evidence level

Licorice Root Extract

Retinaldehyde

Limited evidenceEarly or small studies

Flat tan patches with soft irregular edges across the forehead and upper cheek of an adult with light skin, the surface completely smooth.

Melasma

A small study investigated a specific liquiritin cream.

Uneven Skin Tone

Possible pigment benefit is based on small compound-specific studies.

Uneven Skin Tone

Only the 0.1% group improved the melanin index in the cited trial.

A relaxed forehead with faint shallow horizontal fine lines.

Wrinkles and Fine Lines

Small clinical studies suggest photoaging benefits from particular formulas.

Insufficient evidence

Redness and fine superficial vessels across a light-skinned cheek and nose.

Rosacea

The cited pigment study did not test rosacea.

The front of a forearm on fair skin. Two pale patches with sharp edges sit against lightly tanned skin, and the difference between the patch and the skin around it is subtle.

Vitiligo

The reviewed sources do not establish this ingredient as a treatment for this concern.

Acne

The reviewed sources do not establish this ingredient as a treatment for this concern.

Rosacea

The reviewed sources do not establish this ingredient as a treatment for this concern.

Acne

The cited photoaging study did not establish treatment of acne.

A relaxed forehead with pronounced deep horizontal furrows.

Deep Wrinkles

The reviewed sources do not establish this ingredient as a treatment for this concern.

How it works

Licorice Root Extract mechanism diagram. Contains several active compounds: Glabridin and liquiritin have different actions. May help uneven pigmentation: Extracts and clinical evidence vary. — Open full-size diagram
Diagram explanation and sources
Contains several active compounds: Glabridin and liquiritin have different actions. May help uneven pigmentation: Extracts and clinical evidence vary.
Schematic illustration; not a measurement of skin penetration. Effects vary with ingredient identity and formulation.
Source 1

Retinaldehyde mechanism diagram. Converts to retinoic acid: Skin enzymes can activate retinaldehyde. Changes cell activity: Retinoic acid acts through nuclear receptors. — Open full-size diagram
Diagram explanation and sources
Converts to retinoic acid: Skin enzymes can activate retinaldehyde. Changes cell activity: Retinoic acid acts through nuclear receptors.
Schematic illustration; not a measurement of skin penetration. Effects vary with ingredient identity and formulation.
Source 1

Using both in one routine

Built from where each one usually sits in a routine. Introduce one at a time.

Morning

Step 1

Cleanser

Step 2

Licorice Root ExtractMorning or night

Step 3

Moisturizer

Step 4

Sunscreen

Night

Step 1

Cleanser

Step 2

Licorice Root ExtractMorning or night

Step 3

RetinaldehydeNight

Step 4

Moisturizer

Strengths and forms

Concentrations

Licorice root extract contains multiple compounds, including liquiritin and glabridin. Whole-extract percentages do not reveal the dose of these individual compounds.

Choosing a strength: Look for the named extract or purified compound and evidence for the finished product.

Higher strengths: There is no established universal percentage range or proof that higher whole-extract concentrations improve pigmentation.

Formula matters: A small study of liquiritin cannot establish a recommended strength for every licorice extract, species, or formulation.

0.05% and 0.1% retinaldehyde creams have been compared in a controlled photoaging trial. These percentages cannot be directly compared with retinol or tretinoin.

0.05%

0.1%

Lower studied retinal strength

A cream studied for skin texture and hydration. The result applies to that finished formula.

Higher studied retinal strength

Also studied for photoaging; not better for every measured outcome. Tolerance still determines whether a product suits you.

Choosing a strength: Choose retinaldehyde for its own formula and instructions, not a retinol-to-retinal conversion chart.

Higher strengths: A higher percentage may be harder to tolerate. Stronger products sold commercially do not automatically have stronger comparative clinical evidence.

Formula matters: Encapsulation, stability and the cream or serum base affect delivery. A percentage alone is not a measure of how much reaches skin cells.

Forms

Serum · Cream

When you’ll see results

Approximate windows, not promises.

● Licorice Root Extract

● Retinaldehyde

First few weeks

First few weeksAssess tolerance first; pigment change is usually slower.

First few weeksAssess tolerance and texture; immediate softness can come from the base formula.

4–8 weeks

4–8 weeksSome studied regimens begin showing pigment improvement.

4–8 weeksSubtle changes may appear in some tested products; evidence varies.

8–12 weeks

8–12 weeksA useful review point for benefit and irritation.

8–12 weeksCompare photographs in the same lighting and reassess benefit.

3–6 months

3–6 monthsMany melasma trials assess results over three to four months; recurrence is common.

3–6 monthsPhotoaging trials often need several months; expect modest rather than dramatic change.

6–12 months

6–12 monthsLong-term use depends on the active; follow a monitored plan rather than extending treatment automatically.

6–12 monthsLong-term evidence is limited for many cosmetic actives; continue only if useful.

Safety and sensitive skin

Common reactions

Botanical extracts can cause allergy or stinging; check the complete formula.

Dryness, stinging and peeling can occur; avoid irritated areas.

When to stop

Stop for persistent burning, swelling, blistering or a new rash. Seek urgent care for breathing difficulty or a severe allergic reaction.

Sensitive or inflamed skin

Choose a simple formula and test a small area first. Avoid actively inflamed or broken skin unless the product is specifically directed for it.

Important limits

Do not use a cosmetic product as a substitute for diagnosis of an unexplained, changing or persistent skin problem.

Pregnancy

Data are limited; ask the clinician managing your pregnancy.

Retinoids are conventionally stopped in pregnancy and while trying to conceive. Ask the doctor managing your pregnancy. Azelaic acid is the usual alternative.

How it works

In the skin

On the skin. The finished product delivers licorice root extract in a particular vehicle.

Entering skin. No single molecular mass. The 500 Da guideline cannot be applied to this whole ingredient family or mixture.

Conversion. No activation step is established as necessary for its intended topical role.

Skin response. Compounds such as liquiritin and glabridin have different pigment-related actions; they are not interchangeable extracts.

Additional effects. Proposed pathways do not establish a measured depth of delivery or clinical benefit beyond the studies cited.

On the skin. The finished product delivers retinaldehyde in a particular vehicle.

Entering skin. Below the 500 Da guideline; delivery still depends on the formula, solubility, stability and skin condition. Size does not prove effectiveness or penetration depth.

Conversion. Skin can convert retinaldehyde into retinoic acid.

Skin response. Skin can convert retinaldehyde into retinoic acid, which influences cell activity through retinoid receptors.

Additional effects. Proposed pathways do not establish a measured depth of delivery or clinical benefit beyond the studies cited.

Getting in

No single molecular mass. The 500 Da guideline cannot be applied to this whole ingredient family or mixture.

Below the 500 Da guideline; delivery still depends on the formula, solubility, stability and skin condition. Size does not prove effectiveness or penetration depth.

Product examples

Licorice Root Extract

Anua Azelaic Acid 3 Cica Skin Clarifying Toner

Retinaldehyde

Naturium Retinaldehyde Cream Serum 0.05%
Murad Retinal Resculpt Body Treatment

Common questions

Licorice Root Extract:What should I choose licorice root extract for?

Consider as an optional pigment ingredient; independent clinical evidence is limited.

Licorice Root Extract:How strong is the evidence?

A 20-woman split-face study tested a specific liquiritin cream for four weeks with sun protection. It does not establish that all licorice extracts treat melasma or rosacea.

Retinaldehyde:What should I choose retinaldehyde for?

Consider for photoaged texture; introduce slowly and judge the complete formula.

Retinaldehyde:How strong is the evidence?

A 40-woman trial compared two active strengths without a retinoid-free vehicle group. It supports cautious formula-specific claims, not guaranteed superiority to retinol or acne medicines.

Sources