Structural formula of hyaluronic acid


What is it?

“Proteins (/ˈproʊˌtiːnz/ or /ˈproʊti.ɪnz/) are large biomolecules, or macromolecules, consisting of one or more long chains of amino acid residues.” Wikipedia

What are the effects?

This substance belongs to the groups:

There are a wide variety of animal sourced protein, commonly found as hydrolyzed animal protein, in cosmetic products*. They are especially common in hair care products as most proteins are believed to have a conditioning effect.

Most proteins found in cosmetics are sourced from animals but there are also many that are vegan; derived from plants or manufactured synthetically.


is a structural protein from animal tissues that is commonly obtained from animal skins (ex calves, cattle hides), porcine (pigs), and marine animals (fish).

Supposedly makes hair and skin softer and smoother while functions nourishing, protecting and conditioning. Can not affect skin’s own collagen, according to PETA*.

Egg protein

Simply protein sourced from eggs.

Used in all kinds of hair and skin care products. Functions reportedly as a conditioning agent.


A protein similar to collagen, obtained from animal’s connective tissues. For example from the neck ligaments and aortas (main artery) of cows.

Functions mainly conditioning in all kinds of hair and skin care products but can not, on contrary to popular belief, affect humans skin elasticity, according to PETA.

Hyaluronic Acid

This is what PETA says “When animal-derived, a protein found in umbilical cords and the fluids around the joints.” The substance can also be made synthetically or be obtained from plants.

Hyaluronic acid is used medically, f.ex against dry eyes, dry or scaly skin and. In cosmetics it is mainly used in skin care products and as a dermal filler in cosmetic surgery.


Can be obtained from feathers of slaughtered birds, ground-up horns, quills, sheep wool, and other animal hair – including human hair.

Keratin is common to find in all kinds of hair products such as shampoos, conditioners, balms, and in skin care products such as lotions and creams.

Keratin is restricted for use in Canada, imposed with special conditions that must be met if it is derived from humans or bovine.

Milk protein (Casein, Sodium Caseinate)

This ingredient is a hydrolyzed milk protein, derived from cow milk.

Milk protein can be found in cosmetics such as shampoos, conditioners, and moisturizers. May have antioxidant properties, but is otherwise considered to mainly be a conditioning agent.

How is it used?

See above.

We use the European Commissions definition of Cosmetics:
“Cosmetics range from everyday hygiene products such as soap, shampoo, deodorant, and toothpaste to luxury beauty items including perfumes and makeup”.

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