Cysteine is a non-essential amino acid widely used in cosmetics for its remarkable ability to strengthen and protect hair and nails. It can be derived from animal hair or synthesized from plant-based sources through specific processes.
What is Cysteine and What is It Used For?
Cysteine is an amino acid with a polar side chain, essential for protein synthesis. It plays a key role in cell renewal, maintaining tissue elasticity, and reinforcing protein fibers such as keratin. Its unique structure allows cysteine to form disulfide bonds, which give hair strength, elasticity, and resilience.
Benefits of Cysteine
Strengthening: Cysteine is a precursor to keratin, enhancing the strength and elasticity of hair. Through disulfide bond formation, it protects fibers from breakage and damage, acting as a natural “glue” that keeps hair strands robust.
Antioxidant: As a component of glutathione, one of the most powerful antioxidants, cysteine fights free radicals, reducing oxidative stress and protecting against environmental damage.
Protective: Forms a protective barrier on hair and skin, helping retain natural hydration and shielding against harmful microorganisms, weather, pollution, and chemical treatments.
Regenerating: Especially beneficial for sensitive or irritated skin, cysteine supports conditions like acne and dermatitis, promoting a more even and luminous appearance.
Elasticity and Resilience: Cysteine helps retain moisture in hair fibers, improving density and leaving hair soft, silky, and radiant.
Cysteine vs. Cysteamine: What’s the Difference?
Origin and Structure
Cysteine is an amino acid, while cysteamine is a simplified derivative.
Primary Function
- Cysteine focuses on strengthening and protecting protein structures like hair, skin, and nails.
- Cysteamine is used to break disulfide bonds in hair or reduce skin hyperpigmentation.
Applications
- Cysteine is used in products to reinforce hair during lash and brow lamination.
- Cysteamine is used in lamination products to open the hair cuticle.
In summary: Cysteine supports hair structure and strength, while cysteamine is designed to “open” the hair fibers.
Where Cysteine is Found
Cysteine is commonly included in cosmetic products such as:
- Anti-aging and soothing creams
- Anti-acne lotions
- Pre-shampoo masks
- Lash and brow serums and conditioners
- Hand and nail creams
- After-sun creamsLash and brow lamination products (like LAMI POWDER by My Lamination®)
Cysteine in Lamination
Cysteine is valuable in lamination because it can modify the viscosity of cosmetic products, making treatments more precise and customizable. It also improves lash adherence to silicone pads, ensuring optimal application.
Important: Cysteine does not alter the My Lamination® lamination procedure or timing. Maintain a product-to-powder ratio of 50/50 (1:1) maximum. It can be used to adjust the density of Phase 1 or Phase 2, but never mix the two phases, as each has its own function:
- Phase 1: Opens the hair cuticle
- Phase 2: Neutralizes Phase 1
During lamination, cysteine helps maintain the strength and health of lashes and brows, improving elasticity and protecting fibers from mechanical and chemical damage, ensuring long-lasting, flawless results.
Precautions
Cysteine is generally well-tolerated, but a patch test is recommended to check for adverse reactions. Avoid use if allergic or intolerant to its components. In case of redness or irritation, discontinue use immediately and consult a physician.
Conclusion
Cysteine is a versatile and valuable cosmetic ingredient, offering regenerative, protective, and strengthening properties. Ideal for enhancing the appearance and resilience of hair, skin, and nails, it is a modern, sustainable choice for anyone seeking advanced, eco-conscious beauty solutions.
