A – C

 

A

Acacia Gum

Also known as: Gum arabic, acacia senegal gum
Type: Natural polysaccharide / botanical gum

A water-soluble gum obtained primarily from species of Acacia and Senegalia. In cosmetics, it functions mainly as a film-former, stabilizer, thickener, and skin-conditioning ingredient.

In skincare: Helps form a light film on the skin and can contribute to a smoother, tighter-feeling surface.

Formulation note: Useful in emulsions, masks, serums, and gel systems where film formation or viscosity modification is desired.

Acetyl Glucosamine

Also known as: N-Acetyl-D-glucosamine, NAG
Type: Amino sugar

A naturally occurring derivative of glucose and a component of biological molecules including glycosaminoglycans.

In skincare: Associated with skin barrier support, hydration, and modulation of pigmentation pathways. It is particularly interesting in formulations addressing uneven skin tone.

Skin biology: N-acetylglucosamine is involved in the biosynthesis of hyaluronic-acid-related structures and other glycoconjugates.

Acetyl Hexapeptide-8

Also known as: Argireline
Type: Synthetic peptide

A cosmetic peptide designed to influence mechanisms involved in facial expression lines.

In skincare: Primarily used in formulations targeting the appearance of expression lines and wrinkles.

Formulation note: Peptides are generally incorporated into the cool-down phase of formulations according to supplier recommendations.

Adenosine

Type: Nucleoside

A naturally occurring molecule composed of adenine and ribose and involved in cellular energy metabolism and signaling.

In skincare: Used primarily for its skin-conditioning and anti-aging positioning, particularly in products formulated for the appearance of fine lines.

Alcohol

Also known as: Ethanol, ethyl alcohol
Type: Volatile organic compound

A small alcohol frequently used in cosmetics as a solvent, carrier, antimicrobial aid, and sensory modifier.

In skincare: Can produce a lightweight, rapidly evaporating skin feel and improve dissolution of certain ingredients.

Important distinction: "Alcohol" on an ingredient list does not mean all alcohols are equivalent. Fatty alcohols such as cetyl alcohol and stearyl alcohol behave very differently.

Allantoin

Type: Heterocyclic compound / skin protectant

A compound widely used in cosmetics for its soothing, skin-conditioning, and protective properties.

In skincare: Frequently included in products intended for dry, rough, sensitive, or irritated-feeling skin.

Formulation note: Often used at relatively low concentrations because of its limited solubility.

Aloe Barbadensis Leaf Juice

Common name: Aloe vera
Type: Botanical ingredient

Juice derived from the leaves of Aloe barbadensis.

In skincare: Valued for its hydrating, soothing, and conditioning properties.

Skin biology: Aloe preparations contain polysaccharides and other naturally occurring constituents, although composition varies substantially according to cultivation, processing, and purification.

Alpha-Arbutin

Type: Glycosylated hydroquinone derivative

A naturally occurring glycoside used in cosmetic formulations targeting uneven pigmentation and the appearance of dark spots.

In skincare: Primarily associated with modulation of tyrosinase-related melanogenesis.

Formulation note: Stability, pH, concentration, packaging, and exposure to heat and light are important formulation considerations.

Alpha Hydroxy Acids

Abbreviation: AHAs
Type: Organic acids

A family of acids including glycolic acid, lactic acid, mandelic acid, and citric acid.

In skincare: AHAs can promote exfoliation, smoother texture, improved radiance, and reduction in the appearance of fine lines and uneven pigmentation.

Skin biology: Their effects are strongly influenced by concentration, pH, free-acid availability, formulation vehicle, and exposure time.

Ascorbic Acid

Common name: Vitamin C
Type: Water-soluble antioxidant / organic acid

The biologically active form of vitamin C used in skincare formulations.

In skincare: Supports antioxidant defense and is involved biologically in collagen synthesis. Topical formulations are also used to address the appearance of uneven pigmentation and photodamage.

Formulation challenge: Ascorbic acid is relatively unstable in aqueous formulations and can undergo oxidation when exposed to oxygen, light, heat, and unfavorable pH conditions.

Ascorbyl Glucoside

Type: Vitamin C derivative

A glucoside derivative of ascorbic acid designed to provide improved formulation stability compared with pure ascorbic acid.

In skincare: Used in products targeting antioxidant protection, radiance, and uneven pigmentation.

Azelaic Acid

Type: Dicarboxylic acid

A naturally occurring saturated dicarboxylic acid found in certain grains.

In skincare: Used extensively in formulations addressing blemishes, uneven pigmentation, redness, and irregular skin texture.

Skin biology: Its multifunctional activity makes it particularly interesting for formulations addressing both pigmentation and blemish-prone skin.

B

Bakuchiol

Type: Botanical-derived meroterpene

A naturally occurring compound obtained primarily from Psoralea corylifolia (also known as Cullen corylifolium).

In skincare: Widely used as a botanical ingredient in products targeting fine lines, uneven texture, and signs of photoaging.

Important distinction: Bakuchiol is chemically distinct from retinoids despite often being marketed as a "retinol alternative."

Beeswax

INCI: Cera Alba / Cera Flava
Type: Natural wax

A complex mixture of esters, hydrocarbons, fatty acids, and other components produced by honeybees.

In skincare: Functions primarily as an occlusive, consistency agent, emollient, and structuring material.

Formulation note: Particularly useful in balms, salves, sticks, creams, and anhydrous formulations.

Beta-Glucan

Type: Polysaccharide

A family of glucose polymers found in sources including oats, yeast, fungi, and certain plants.

In skincare: Used for hydration, soothing, skin conditioning, and barrier-supportive formulations.

Skin biology: Molecular structure and source influence biological behavior; not all beta-glucans are functionally identical.

Betaine

Also known as: Trimethylglycine
Type: Osmolyte / amino-acid derivative

A naturally occurring zwitterionic compound involved in cellular osmotic regulation.

In skincare: Functions primarily as a humectant and skin-conditioning agent.

Formulation benefit: Can contribute to a softer skin feel and help reduce the harsh sensory characteristics of some cleansing systems.

Biotin

Common name: Vitamin B7
Type: Water-soluble vitamin

A cofactor required for several carboxylation reactions involved in metabolism.

In skincare: Used in some cosmetic formulations for hair and skin conditioning, although topical cosmetic applications should not be confused with systemic nutritional supplementation.

Bisabolol

Type: Sesquiterpene alcohol

A naturally occurring compound found notably in German chamomile and other botanical sources.

In skincare: Valued primarily for its soothing and skin-conditioning properties.

Formulation note: Frequently used in products designed for sensitive or easily irritated skin.

Butylene Glycol

Type: Diol / solvent / humectant

A multifunctional cosmetic ingredient used extensively in skincare formulations.

In skincare: Helps attract and retain water while also functioning as a solvent, viscosity modifier, and formulation aid.

Formulation benefit: Can improve spreadability and help dissolve or distribute other ingredients.

C

Caffeine

Type: Methylxanthine alkaloid

A naturally occurring stimulant found in coffee, tea, cacao, and other plants.

In skincare: Used primarily for its antioxidant, conditioning, and de-puffing positioning, particularly in eye-area formulations.

Ceramides

Type: Sphingolipids / skin lipids

A family of lipids naturally present within the stratum corneum.

In skincare: Ceramides are fundamental to barrier structure and water-loss regulation.

Skin biology: Together with cholesterol and free fatty acids, ceramides form organized extracellular lipid structures between corneocytes.

Formulation note: Ceramide type, concentration, delivery system, and lipid composition all influence performance.

Cetyl Alcohol

Type: Fatty alcohol

A long-chain fatty alcohol derived from natural or synthetic sources.

In skincare: Functions as an emollient, thickener, consistency agent, and co-emulsifier.

Important distinction: Despite containing the word "alcohol," cetyl alcohol is not comparable to volatile alcohols such as ethanol.

Cetearyl Alcohol

Type: Fatty alcohol mixture

Usually composed primarily of cetyl alcohol and stearyl alcohol.

In skincare: Provides emollience, viscosity, structure, and stability to creams and lotions.

Formulation note: Commonly used with emulsifiers to create rich, stable cream textures.

Cetearyl Glucoside

Type: Nonionic emulsifier

An emulsifying ingredient derived from fatty alcohols and glucose.

In skincare: Helps combine oil and water phases and contributes to the structure and sensory profile of emulsions.

Citric Acid

Type: Alpha hydroxy acid / organic acid

A naturally occurring organic acid found widely in citrus fruits and other biological systems.

In skincare: Functions primarily as a pH adjuster and chelating agent, and at suitable concentrations can also contribute to exfoliation.

Formulation note: Its cosmetic role depends heavily on concentration and final formulation pH.

Citric Acid Esters

Type: Ester derivatives

Derivatives of citric acid used in cosmetic formulations for various functional purposes.

In skincare: Depending on the specific ester, these ingredients may function as emollients, solvents, plasticizers, or formulation aids.

Collagen

Type: Structural protein

The principal structural protein family of connective tissues.

In skin: Collagen provides much of the structural framework of the dermal extracellular matrix and contributes to firmness and tensile strength.

Topical skincare: Hydrolyzed collagen and collagen-derived ingredients primarily function as film-forming and conditioning agents. Topically applied collagen should not be interpreted as directly replacing dermal collagen.

Colloidal Oatmeal

INCI: Avena Sativa Kernel Flour
Type: Botanical / finely milled oat preparation

A finely milled preparation of oat kernels containing proteins, lipids, polysaccharides, and other constituents.

In skincare: Used for soothing, moisturizing, cleansing, and skin-protective formulations, particularly for dry and sensitive-feeling skin.

Coenzyme Q10

Also known as: Ubiquinone
Type: Quinone / antioxidant

A naturally occurring lipid-soluble molecule involved in mitochondrial electron transport.

In skincare: Used primarily as an antioxidant and skin-conditioning ingredient in formulations targeting visible signs of environmental and oxidative stress.

Copper Peptides

Common example: Copper tripeptide-1
Type: Bioactive peptide complex

Peptides capable of binding copper ions and used in cosmetic formulations targeting the appearance of aging skin.

In skincare: Associated with skin conditioning, repair-supportive formulations, and the appearance of firmness and elasticity.

Formulation note: Peptide chemistry, copper availability, pH, and interactions with other formulation ingredients require careful consideration.

Cyclodextrins

Type: Cyclic oligosaccharides

Ring-shaped carbohydrate molecules capable of forming inclusion complexes with certain hydrophobic molecules.

In skincare: Can be used as solubilizing, stabilizing, odor-control, or delivery-supporting agents.

Formulation science: Their ability to encapsulate selected molecules makes them particularly interesting in advanced cosmetic delivery systems.