Keratin Smooth Shampoo

The base most products are built on. It carries the other ingredients and has no safety concern.

A common foaming cleanser, milder than SLS. Fine for most people in a rinse-off product.

Dimethiconol is a silicone emollient closely related to dimethicone, used to add slip and a smooth finish to creams and serums. It shares dimethicone's long-standing safety record and is considered non-sensitizing and non-comedogenic in typical use.

A coconut-derived amphoteric surfactant used to boost foam and mildness in cleansers and shampoos. CIR has reviewed it as safe as used, but it is one of the more established contact-allergy triggers in personal care, usually traced to manufacturing impurities such as amidoamine and dimethylaminopropylamine (DMAPA) rather than the betaine itself. People with a history of eyelid or scalp dermatitis are more likely to react.

Ordinary salt, used in surfactant-based products like shampoos and body washes to adjust viscosity by interacting with the surfactant micelles. It has no meaningful toxicity concern at cosmetic use levels; the main practical downside is that too much can make a formula feel less mild.

The sodium salt of benzoic acid, used as a preservative in both foods and cosmetics. Decades of safety review support its use at typical cosmetic concentrations, with mild irritation the main reported issue in sensitive skin.

Used in tiny amounts to set a product to skin-friendly pH. No concern at those levels.

Carbomer is a synthetic polymer used purely to thicken and stabilize gels and lotions, with negligible skin penetration due to its large molecular size. Safety reviews have found low toxicity and minimal irritation potential even in leave-on use.

A silicone-based polymer with amino groups that deposits on hair to provide conditioning and smoothing benefits. It is extensively used in hair care products with a long track record of safe use in rinse-off formulations.

A wax-like ester of ethylene glycol and stearic acid used purely to thicken shampoo/conditioner and give it a pearly opaque look; it has no cleansing or active role. CIR found it non-sensitizing and non-irritating even at high test concentrations, and decades of manufacturer exposure data show no reported health effects.

A modified guar gum used to thicken and stabilize emulsions and gels. It is derived from guar beans and is well tolerated when applied topically. It is common in skincare formulas where a smooth texture is valued.

A lightweight, volatile silicone that gives serums and primers their silky slip and quick-evaporating finish. Human safety data are reassuring; the EU restriction on this ingredient in rinse-off products is about environmental persistence in waterways, not skin safety.

A chelating agent that binds trace metal ions to keep formulas stable and preservatives working properly. It is not a functional skincare "active" and only a very small amount is used, with minimal skin penetration expected.

A coconut-derived fatty acid amide used as a foam booster and thickener in shampoos and washes. It is a recognized, if uncommon, contact sensitizer, and because it belongs to the same ethanolamine family reviewed alongside cocamide DEA, formulators are advised to keep it free of nitrosamine-forming contaminants; well-made products with controlled impurity levels are considered acceptable for rinse-off use.

A widely used preservative, safe at the legal limit of 1% or less. Often the "paraben-free" replacement.

A naturally occurring mineral silicate that adds shimmer and light-diffusing properties to cosmetics. Cosmetic-grade mica is well tolerated and should be free of asbestos and talc contamination.

A quaternary ammonium salt used as a conditioning and antistatic agent in hair products. It has been extensively documented as safe in cosmetics when used in typical rinse-off formulations.

A mineral UV filter and white pigment used in sunscreens and makeup. It sits on the skin surface rather than being absorbed, and major regulators consider it safe for topical cosmetic use.

A humectant that draws water into the skin. One of the best-studied, best-tolerated ingredients in personal care.

A larger, gentler alpha hydroxy acid than glycolic acid, used to exfoliate and to draw in moisture. It can still cause stinging or increased sun sensitivity at higher concentrations, so daytime SPF use is sensible, but it is generally better tolerated than glycolic acid.

A mineral thickener and anti-caking agent widely used in sunscreens and cosmetics to control texture and prevent ingredient separation. CIR has reviewed silica in cosmetic use and found no basis for concern at the levels used topically.

A protein fragment derived from animal keratin that helps hair retain moisture and improves strength and shine. It is well tolerated across hair types and does not carry the allergen risk of plant-derived hydrolyzed proteins.

A strong alkali used in tiny amounts to adjust the pH of cosmetics to safe, skin-friendly levels. At the pH found in finished products, sodium hydroxide is neutralized and well tolerated.

A fatty-acid and tocopherol-rich plant oil used as a hair and skin emollient; CIR's review of plant-derived fatty acid oils found no evidence of irritation or sensitization and a long history of safe use in food and cosmetics.

A rich plant butter pressed from shea tree nuts, valued for softening and cushioning dry skin. It is generally well tolerated, though very rare allergic reactions have been reported and people with tree nut allergies who are cautious may want to patch test first.

Technically a liquid wax ester rather than a true oil, jojoba closely resembles skin's own sebum and absorbs without feeling greasy. It is well tolerated across skin types, including acne-prone skin, with no significant irritation or comedogenicity signal in the available data.

A lightweight botanical oil from marula tree seeds, valued for softening and conditioning the skin. It is generally well tolerated across skin types.

An essential amino acid in salt form, used as a humectant to support skin hydration. Lysine is a recognized component of skin proteins and natural moisturizing factor, with established safe use in cosmetic formulations.

A halogenated preservative used to prevent microbial growth in leave-on and rinse-off cosmetics. Published assessments consider it safe at permitted use levels, but it is a recognized contact allergen; people with known sensitizer profiles or a history of cosmetic dermatitis should patch-test products containing it.

A small-dose synthetic antioxidant that prevents oils and fragrance in a formula from oxidizing. Not shown to pose a toxicological risk at the levels used in cosmetics.

A widely used, gentle preservative also common in food. It is generally well tolerated, though it can occasionally cause mild, transient irritation in people with already-compromised or very reactive skin.