Science-First Database

Ingredient Directory

Explore 73 ingredient guides with routine context, safety notes, and plain-English explanations. Use the directory to compare classic actives, newer trends, barrier-support ingredients, and prescription-adjacent options before you add them to a routine.

Next-Generation Ingredients

Bio-Retinol Revolution
Gentle plant-derived retinoid alternatives like Bakuchiol.
Exosome Therapy
Advanced vesicle-based delivery for skin-barrier regeneration.
AI-Personalized Actives
Dermatologist-tailored formulations optimized for concern targets.

Trending & Highly Effective

Hyaluronic Acid
Deep Hydration
Collagen
Firmness & Elasticity
Vitamin C
Brightening & Protection
Glutathione
Melanin Inhibition & Skin Brightening
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Showing 112 of 73 ingredients

Trending
Evidence: High (15+ Studies)

Hyaluronic Acid

Hydration

Hyaluronic acid is a naturally occurring substance in the human body that has the remarkable ability to hold up to 1,000 times its weight in water. This makes it an exceptional humectant for skincare applications, providing intense hydration and helping to maintain skin plumpness and elasticity.

All skin typesDehydrated skinSensitive skin
Trending
Evidence: Moderate (8+ Studies)

Collagen

Anti-Aging

Collagen is the most abundant protein in our skin, providing structure, firmness, and elasticity. As we age, collagen production naturally decreases by 1% per year after age 20, leading to wrinkles and sagging. Topical collagen peptides and collagen-boosting ingredients help maintain skin firmness and hydration.

Mature skinLoss of firmnessFine lines
Trending
Evidence: High (15+ Studies)

Vitamin C

Antioxidant

Vitamin C is a potent antioxidant that brightens skin, stimulates collagen production, and provides protection against environmental damage. It's particularly powerful when paired with Ferulic Acid and Vitamin E, which stabilize the molecule and enhance its effectiveness.

Dull skinHyperpigmentationEnvironmental protection
TrendingNew
Evidence: Moderate (8+ Studies)

Glutathione

Brightening & Antioxidant

Glutathione is a tripeptide composed of three amino acids (cysteine, glutamic acid, and glycine). Known as "the master antioxidant," it is highly effective at neutralizing free radicals and inhibiting tyrosinase, the enzyme responsible for melanin production, making it a gold-standard ingredient for fading dark spots and evening skin tone.

HyperpigmentationDark spots / MelasmaDullness
Trending
Evidence: High (15+ Studies)

Retinol

Anti-Aging

Retinol is a form of vitamin A that is considered the gold standard in anti-aging skincare. It accelerates cell turnover, stimulates collagen production, and helps reduce fine lines, wrinkles, and hyperpigmentation.

Fine linesWrinklesUneven texture
Trending
Evidence: High (15+ Studies)

Niacinamide

Barrier Support

Niacinamide is a form of Vitamin B3 that's incredibly versatile and well-tolerated by most skin types. It's the perfect beginner-friendly ingredient that regulates oil production, minimizes pores, strengthens the skin barrier, and reduces inflammation.

All skin typesOily skinLarge pores
TrendingNew
Evidence: Moderate (8+ Studies)

PDRN (Salmon DNA)

Regenerative

PDRN (Polydeoxyribonucleotide) is a DNA fragment extracted from salmon semen. It is highly valued in regenerative medicine and anti-aging skincare for its remarkable ability to stimulate cellular repair, boost collagen synthesis, and accelerate wound healing without causing allergic reactions.

Mature skinDamaged barrierPost-procedure skin
Trending
Evidence: Moderate (8+ Studies)

Glass Skin Mask

K-Beauty Treatment

Glass skin masks are intensive hydrating treatments designed to achieve the Korean beauty ideal of "glass skin" - a complexion so smooth, clear, and luminous it resembles glass. These masks typically contain multiple molecular weights of hyaluronic acid, peptides, and brightening ingredients.

Dehydrated skinDull complexionSpecial occasions
TrendingNew
Evidence: Moderate (8+ Studies)

NAD+ Skincare

Cellular Longevity

NAD+ (Nicotinamide Adenine Dinucleotide) is a vital coenzyme found in every living cell, responsible for cellular energy production (ATP) and DNA repair. As skin cells age, NAD+ levels drop by up to 50% by age 50. Topical NAD+ and its precursors (like NR and NMN) help restore cellular energy, repair environmental damage, and reverse signs of aging.

Fine lines and wrinklesDull, fatigued skinEnvironmental damage (UV/pollution)
TrendingNew
Evidence: Moderate (8+ Studies)

Beta-Glucan

Hydration & Barrier

Beta-Glucan is a natural polysaccharide derived from oats, yeast, or mushrooms. It is a powerful humectant that is 20% more hydrating than hyaluronic acid at the same concentration, while also offering superb anti-inflammatory, soothing, and barrier-repair properties.

Dehydrated skinSensitive skinRedness-prone skin
TrendingNew
Evidence: Moderate (8+ Studies)

Reishi Mushroom Extract

Soothing & Hydration

Reishi and Tremella are adaptogenic mushrooms prized in traditional herbal medicine and modern skincare. Reishi (Ganoderma Lucidum) is a powerful anti-inflammatory and antioxidant that calms redness and irritation, while Tremella (Snow Mushroom) acts as a superior humectant, holding up to 500 times its weight in water with molecular structures smaller than hyaluronic acid for deeper hydration.

Sensitive skinRedness / RosaceaDehydrated skin
Trending
Evidence: High (15+ Studies)

Azelaic Acid

Multi-Benefit Active

Azelaic acid is a naturally occurring dicarboxylic acid found in grains like wheat and barley. It's a gentle yet effective multi-tasking ingredient that addresses acne, rosacea, and hyperpigmentation simultaneously, making it ideal for sensitive skin that can't tolerate stronger actives.

AcneRosaceaHyperpigmentation

How to Use This Directory

Start with the skin goal you actually care about, then compare how different ingredients fit into a real routine. A brightening ingredient like Alpha Arbutin solves a different problem than a retinoid like Adapalene or a barrier-support ingredient like Glycerin.

When you open an ingredient page, focus on timing, routine placement, common watchouts, and the combinations section before you decide whether the ingredient belongs in your routine.

Ingredient Penetration Depths

Understanding how deep skincare ingredients can reach

Stratum Corneum

Outermost protective layer

Depth: 0.01-0.02mm

High MW Hyaluronic Acid

Molecular Size: 1,000-1,800 kDa

Mineral Sunscreens

Molecular Size: Particulate

Silicones

Molecular Size: Film-forming

Ceramides

Molecular Size: 500-1,000 Da

Epidermis

Living skin cells, no blood vessels

Depth: 0.05-0.1mm

Medium MW Hyaluronic Acid

Molecular Size: 100-1,000 kDa

Niacinamide

Molecular Size: 122 Da

Vitamin C Derivatives

Molecular Size: 200-500 Da

AHAs (Glycolic Acid)

Molecular Size: 76 Da

Dermis

Collagen, elastin, blood vessels

Depth: 0.5-3mm

Low MW Hyaluronic Acid

Molecular Size: 10-100 kDa

Retinol

Molecular Size: 286 Da

Peptides

Molecular Size: 500-1,500 Da

L-Ascorbic Acid

Molecular Size: 176 Da

Factors Affecting Penetration

Molecular Weight

Smaller molecules (under 500 Da) penetrate deeper. The 500 Da rule states that molecules larger than this rarely penetrate beyond the stratum corneum.

Formulation

Delivery systems like liposomes, nanoparticles, and certain solvents can help larger molecules penetrate deeper into skin layers.

Skin Condition

Damaged or compromised skin barriers allow deeper penetration, while intact barriers are more selective about what passes through.

Targeted Solutions for Common Skin Concerns

Science-backed ingredients ranked by effectiveness for specific concerns

Hyperpigmentation

Vitamin C
8-12 weeks92%
Tranexamic Acid
8-12 weeks87%
Alpha Arbutin
12+ weeks78%
Kojic Acid
12+ weeks75%
Niacinamide
8-12 weeks70%

Pro Tips:

  • Always use sunscreen
  • Consistency is key
  • Combine ingredients for best results

Acne

Salicylic Acid
4-8 weeks90%
Benzoyl Peroxide
4-6 weeks88%
Azelaic Acid
8-12 weeks85%
Niacinamide
8 weeks82%
Retinoids
12 weeks80%

Pro Tips:

  • Don't over-cleanse
  • Avoid picking or squeezing
  • Hydration is still important

Fine Lines & Wrinkles

Retinol
12+ weeks95%
Peptides
12+ weeks85%
Vitamin C
12+ weeks80%
Bakuchiol
12+ weeks75%
AHAs
8-12 weeks70%

Pro Tips:

  • Prevention is easier than correction
  • Sunscreen is your best anti-aging tool
  • Consistency over time yields results

Dryness & Dehydration

Hyaluronic Acid
Immediate95%
Glycerin
Immediate90%
Ceramides
2-4 weeks88%
Squalane
Immediate85%
Panthenol
Immediate82%

Pro Tips:

  • Apply to damp skin
  • Use humidifier in dry climates
  • Layer hydrating products

Sensitivity & Redness

Centella Asiatica
2-4 weeks90%
Azelaic Acid
4-8 weeks85%
Niacinamide
4-8 weeks82%
Oat Extract
Immediate80%
Allantoin
2-4 weeks75%

Pro Tips:

  • Minimize active ingredients
  • Patch test everything
  • Focus on barrier repair

Enlarged Pores

Niacinamide
4-8 weeks88%
Retinol
12+ weeks85%
Salicylic Acid
4-8 weeks82%
Clay
Temporary75%
AHAs
8-12 weeks70%

Pro Tips:

  • Double cleanse to remove oil
  • Don't skip moisturizer
  • Consistent exfoliation helps

Understanding Efficacy Ratings:

Efficacy percentages are based on clinical studies, research data, and expert consensus. Individual results may vary based on skin type, product formulation, and consistent use.

90%+ Efficacy

Gold standard ingredients with substantial research

80-89% Efficacy

Highly effective with strong clinical backing

70-79% Efficacy

Effective supporting ingredients

Regional Climates & Routine Focus

How climate variables like humidity, pollution, and UV indices shape regional product choices and barrier requirements.

🇺🇸 United States

High daytime UV and urban oxidation demands strong antioxidant layers like stabilized Vitamin C.

Antioxidant Focus

🇰🇷 South Korea

Focus on hydration stacking and lightweight humectants (Glycerin, Centella) to get the clean glass-skin shine.

Hydration Stacking

🇬🇧 United Kingdom

Unpredictable damp humidity requires redness soothing (Oat, Panthenol) and light barrier seals.

Redness & Soothing

🇨🇦 Canada

Severe dry winter periods reward rich lipids (Ceramides, Squalane) to seal transepidermal water loss.

Barrier Shielding