Ingredient education

Skincare Ingredient Glossary

Every active we carry, explained by our skincare experts, with the products that use it.

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Hyaluronic Acid

Best for

Dryness, dehydration, plumping

Niacinamide

Best for

Redness, enlarged pores, oil control

Peptides

Best for

Firmness, fine lines, barrier support

Retinol

Best for

Fine lines, acne, stretch marks

Salicylic Acid

Best for

Acne, blackheads, congestion

Vitamin C

Best for

Dark spots, dullness, environmental damage

The full glossary

31 entries, A to Z. Every one reviewed by our licensed skincare professionals.

AHAAlso known as alpha hydroxy acids: glycolic, lactic, mandelic Exfoliation, uneven texture, dullness
Algae extractAlso known as seaweed, kelp, spirulina extracts Hydration, soothing, antioxidant support
Aloe veraAlso known as aloe barbadensis leaf juice Calming, post-sun and post-procedure care
AntioxidantsIncludes vitamin C, vitamin E, ferulic acid, resveratrol Environmental and free radical protection
ArbutinAlso known as alpha arbutin, bearberry extract Dark spots, uneven tone
ArnicaAlso known as arnica montana flower extract Bruising, swelling, recovery
Azelaic acidAlso known as azeloglicina, potassium azeloyl diglycinate Redness, rosacea, breakouts
BakuchiolAlso known as babchi seed extract Fine lines for retinol-sensitive skin
BemotrizinolAlso known as Tinosorb S Broad spectrum UV filter
Benzoyl peroxideAlso known as BPO Active breakouts, body acne
BHAAlso known as beta hydroxy acid: salicylic acid, willow bark Blackheads, oil, congested pores
BiotinAlso known as vitamin B7 Skin, hair, and nail support
CaffeineAlso known as coffea arabica extract Puffiness, dark circles
Centella asiaticaAlso known as cica, tiger grass, madecassoside Barrier repair, calming
CeramidesAlso known as ceramide NP, AP, EOP Dryness, compromised barrier
Chemical sunscreen filtersIncludes avobenzone, homosalate, octisalate Lightweight daily sun protection
ClayAlso known as kaolin, bentonite Oil control, congestion
CollagenAlso known as hydrolyzed collagen, collagen peptides Surface hydration, plumping
Copper peptidesAlso known as GHK-Cu Firmness, elasticity, repair
CysteamineAlso known as cysteamine hydrochloride Melasma, stubborn pigmentation
DefensinsAlso known as alpha and beta defensin peptides Renewal, fine lines
DNA repair enzymesAlso known as photolyase, endonuclease Visible sun damage
EctoinAlso known as ectoine Sensitive skin, hydration, barrier defense
EnzymesAlso known as papain, bromelain, pumpkin enzyme Gentle exfoliation
ExosomesAlso known as exosome complexes, growth factor media Post-procedure recovery, regeneration
Hyaluronic AcidAlso known as sodium hyaluronate, hyaluronan Dryness, dehydration, plumping
NiacinamideAlso known as vitamin B3, nicotinamide Redness, enlarged pores, oil control
PeptidesAlso known as signal peptides, matrixyl, argireline Firmness, fine lines, barrier support
RetinolAlso known as retinoids, vitamin A, retinyl palmitate Fine lines, acne, stretch marks
Salicylic AcidAlso known as BHA, beta hydroxy acid, willow bark extract Acne, blackheads, congestion
Vitamin CAlso known as L-ascorbic acid, ascorbyl glucoside, THD ascorbate Dark spots, dullness, environmental damage

The glossary continues through Z, from ferulic acid to zinc oxide.

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Ingredient FAQs

Both are retinoids, vitamin A derivatives that speed up cell turnover. Retinol is available over the counter and converts to retinoic acid in the skin, so it works gradually with less irritation. Tretinoin is the prescription-strength form and acts faster, but often with more dryness and peeling.

Yes, most skin tolerates both when they are used at different times of day. Apply vitamin C in the morning under sunscreen and retinol at night. If you are new to actives, introduce them one at a time over two to three weeks.

Azelaic acid, niacinamide, hyaluronic acid, and mineral sunscreens are widely considered safe during pregnancy. Retinoids and hydroquinone should be paused until after nursing. Always confirm your routine with your OB or dermatologist.

Check the ingredient list for parfum, fragrance, or essential oils, usually near the end. Fragrance-free means no added scent, while unscented products may use a masking fragrance. Every product page on our site lists the full ingredient list so you can verify before you buy.

Mineral filters like zinc oxide and titanium dioxide sit on the skin and deflect UV, and they are the gentler pick for reactive skin. Chemical filters like avobenzone and bemotrizinol absorb UV and tend to feel lighter and clearer. Many modern formulas combine both.

Reviewed by our licensed skincare professionals

Reviewer Name, Licensed Esthetician · Reviewer Name, MD