Keratin used in beauty treatments is usually from these animal parts. While it is a natural protein, these products are made with several other added ingredients. Keratin treatments typically contain a chemical called formaldehyde. The American Cancer Society warns that formaldehyde is a known carcinogen.

Is there keratin without formaldehyde?

Real-talk time: There's no such thing as a truly chemical-free hair-straightening treatment. For a keratin treatment to give you shiny, straighter, frizz-free hair for months, it must contain formalin or another chemical in the same family.

Do all keratin treatments have formaldehyde?

Part of the concern with keratin treatments revolve around one of the ingredients found in most traditional salon formulas: formaldehyde. ... But these treatments don't actually contain formaldehyde, because, well, it's a known carcinogen.