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Cysteine

Description

Cysteine is a non-essential amino acid that plays a crucial role in skincare formulations and dermatological treatments. This sulfur-containing compound is a powerful antioxidant and a key component in the synthesis of glutathione, a major cellular antioxidant. In skincare, cysteine is valued for its ability to neutralize free radicals, protecting the skin from oxidative stress and environmental damage.

Topically applied cysteine can help improve skin texture and tone by promoting collagen synthesis and supporting the skin's natural repair processes. It has been shown to inhibit tyrosinase activity, potentially reducing hyperpigmentation and evening out skin tone. Cysteine's keratolytic properties make it useful in treating certain skin conditions like psoriasis and ichthyosis.

In hair care, cysteine is essential for maintaining the strength and structure of keratin, the primary protein in hair. It's often used in hair treatments to improve hair health and reduce breakage. Cysteine's ability to break and reform disulfide bonds makes it a key ingredient in some hair straightening treatments.

When formulating with cysteine, it's important to consider its stability and pH sensitivity. It's most effective in slightly acidic formulations and should be protected from oxidation to maintain its efficacy.