Ingredient science
Every ingredient, explained.
A working library of skincare and supplement ingredients. What each one actually does, how it works in the body, side effects to know, and product picks that hold up in 2026.
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skincare
Retinol
Vitamin A derivative that speeds cell turnover.
skincare
Niacinamide
Vitamin B3 that calms redness and shrinks visible pores.
skincare
Hyaluronic Acid
Humectant that binds water in the skin.
skincare
Ceramides
Lipids that make up the skin barrier.
skincare
Peptides
Short chains of amino acids that signal collagen.
skincare
Vitamin C
Antioxidant that brightens skin and fights free radicals.
skincare
Azelaic Acid
Dicarboxylic acid that treats acne and rosacea.
skincare
Salicylic Acid
Beta hydroxy acid that unclogs pores.
skincare
Benzoyl Peroxide
Antibacterial that kills acne-causing bacteria.
skincare
Glycolic Acid
Alpha hydroxy acid that exfoliates the surface.
skincare
Lactic Acid
Gentle AHA suitable for sensitive skin.
skincare
Mandelic Acid
Larger AHA molecule with less irritation.
skincare
Tranexamic Acid
Amino acid derivative for stubborn pigmentation.
skincare
Alpha Arbutin
Skin-lightening derivative of hydroquinone.
skincare
Kojic Acid
Mushroom-derived tyrosinase inhibitor.
skincare
Bakuchiol
Plant-based alternative to retinol.
skincare
Squalane
Non-comedogenic oil that mimics skin lipids.
skincare
Panthenol
Provitamin B5 that soothes and repairs.
skincare
Allantoin
Comfrey-derived soothing agent.
skincare
Centella Asiatica
Traditional herb that calms and heals.
skincare
Snail Mucin
Filtrate rich in glycoproteins and hyaluronic acid.
skincare
Zinc Oxide
Mineral UV filter and soothing agent.
skincare
Titanium Dioxide
Mineral UV filter for sensitive skin.
skincare
Vitamin E
Lipid-soluble antioxidant.
skincare
Ferulic Acid
Plant antioxidant that stabilizes vitamin C.
skincare
Resveratrol
Grape-derived antioxidant.
skincare
Copper Peptides
Copper-bound peptides that support healing.
skincare
Argireline
Hexapeptide that relaxes expression lines.
skincare
Matrixyl
Palmitoyl pentapeptide that stimulates collagen.
skincare
PHA (Polyhydroxy Acid)
Large molecule acid for sensitive exfoliation.
skincare
Urea
Humectant and mild keratolytic.
skincare
Green Tea Extract
EGCG-rich antioxidant.
skincare
Sulfur
Mineral that dries out acne lesions.
skincare
Adapalene
OTC third-generation retinoid.
skincare
Ectoin
Amino acid derivative that protects against stress.
skincare
Beta-Glucan
Polysaccharide that soothes and hydrates.
skincare
Colloidal Oatmeal
Finely ground oats that calm inflammation.
skincare
Chamomile Extract
Bisabolol-rich soothing plant extract.
skincare
Aloe Vera
Traditional soothing plant.
skincare
Willow Bark Extract
Natural source of salicylates.
skincare
Papaya Enzyme
Papain protease that dissolves dead skin.
skincare
Pineapple Enzyme
Bromelain protease.
skincare
Rosehip Oil
Fatty acid rich oil with natural retinoic acid.
skincare
Jojoba Oil
Wax ester that mimics human sebum.
skincare
Argan Oil
Vitamin E rich oil from Morocco.
skincare
Marula Oil
African oil rich in oleic acid.
skincare
Squalene
Naturally occurring skin lipid.
skincare
Sodium Hyaluronate
Salt form of hyaluronic acid.
skincare
Retinal (Retinaldehyde)
One step from retinoic acid.
skincare
Hydroquinone
Prescription-strength pigment inhibitor.
skincare
Sunscreen (Chemical Filters)
Organic UV filters like avobenzone and octinoxate.
skincare
Retinyl Palmitate
The mildest retinoid ester.
skincare
Collagen (Topical)
Protein used for surface hydration.
supplement
Collagen (Oral)
Hydrolyzed peptides for skin and joints.
supplement
Biotin
B vitamin marketed for hair and nails.
supplement
Ashwagandha
Adaptogenic herb for stress and cortisol.
supplement
Magnesium
Essential mineral for muscle and nerve function.
supplement
Omega-3 (Fish Oil)
EPA and DHA fatty acids.
supplement
Vitamin D3
Fat-soluble vitamin from sun and supplements.
supplement
Vitamin B12
Essential vitamin for nerves and blood cells.
supplement
Iron
Essential mineral for red blood cells.
supplement
Zinc
Trace mineral for immunity and skin.
supplement
Creatine
Amino acid derivative for muscle energy.
supplement
L-Theanine
Green tea amino acid for calm focus.
supplement
Rhodiola Rosea
Adaptogen from cold climates.
supplement
Turmeric (Curcumin)
Anti-inflammatory root.
supplement
Probiotics
Live microorganisms for gut health.
supplement
Prebiotics
Fibers that feed gut bacteria.
supplement
Coenzyme Q10
Mitochondrial antioxidant.
supplement
NAC (N-Acetyl Cysteine)
Amino acid precursor to glutathione.
supplement
Melatonin
Sleep-regulating hormone.
supplement
5-HTP
Serotonin precursor.
supplement
GABA
Inhibitory neurotransmitter.
supplement
Berberine
Plant compound for blood sugar and metabolism.
supplement
Quercetin
Flavonoid antioxidant.
supplement
Vitamin K2 (MK-7)
Vitamin that directs calcium.
supplement
Vitamin A (Retinol Oral)
Fat-soluble vitamin.
supplement
Selenium
Trace mineral for thyroid and immunity.
supplement
Iodine
Trace mineral for thyroid hormones.
supplement
Chromium
Trace mineral marketed for blood sugar.
supplement
L-Carnitine
Amino acid for fatty acid transport.
supplement
Beta-Alanine
Amino acid that buffers muscle acid.
supplement
Glutamine
Amino acid for gut and muscle recovery.
supplement
Whey Protein
Fast-absorbing complete protein.
supplement
Casein Protein
Slow-releasing milk protein.
supplement
Pea Protein
Plant-based protein.
supplement
Beta-Carotene
Provitamin A carotenoid.
supplement
Lycopene
Tomato carotenoid antioxidant.
supplement
Astaxanthin
Algae-derived carotenoid.
supplement
Milk Thistle
Silymarin-rich herb.
supplement
Saw Palmetto
Palm berry marketed for hair and prostate.
supplement
Nettle Root
Herb that may block DHT.
supplement
Pumpkin Seed Oil
Zinc and phytosterols.
haircare
Minoxidil
FDA-approved topical for hair loss.
haircare
Finasteride
Oral DHT-blocker.
haircare
Rosemary Oil
Essential oil studied for hair growth.
haircare
Ketoconazole
Antifungal shampoo ingredient.
haircare
Caffeine (Topical)
Stimulant applied to scalp.
haircare
Argan Oil (Hair)
Vitamin E rich oil for hair.
haircare
Castor Oil
Ricinoleic acid rich oil.