Science
Mechanism of Action
Tetrasodium Disuccinoyl Cystine functions by elevating intracellular adenosine triphosphate (ATP) synthesis within keratinocytes, the primary cells of skin, hair, and nails. This surge in ATP provides essential metabolic energy, vital for the healthy functioning of hair bulbs and nail matrices, thereby contributing to reduced hair loss and enhanced nail growth. Structurally, its succinic acid-modified cystine moiety allows it to specifically target and bind to compromised regions within hair fibers, from their outermost cuticle to the inner cortex. This interaction facilitates the rebuilding of keratin architecture, improving hair's intrinsic strength and substantivity against environmental stressors and chemical damage. Furthermore, it can contribute to a more compact stratum corneum, strengthening skin barrier function and potentially inhibiting dandruff formation. The enzymatic succinylation is thought to optimize cystine's cellular uptake and metabolic stimulation.
Research
Clinical Evidence
Medium confidence0.25%
Transparency
Dusting Analysis
The Formula
Formulation
Stability
While the parent L-Cystine exhibits reduced solubility at neutral pH and can precipitate at higher concentrations, specific optimal pH and stability data for Tetrasodium Disuccinoyl Cystine are not explicitly detailed. However, related amino acids like cysteine show enhanced solubility at pH values significantly deviating from its isoelectric point of 5.1, and cysteine-capped dispersions remain stable above pH 7. Further research into the derivative's precise stability profile is recommended for optimal formulation.
Safety
Safety Profile
This ingredient is authorized for cosmetic use in major global markets including the EU, USA, and Canada. Reputable safety databases like EWG Skin Deep assess it with 'Low' concern for potential cancer, allergies & immunotoxicity, and developmental & reproductive toxicity. SkinSAFE categorizes it broadly as 'SAFE' for various sensitive applications (e.g., Teen, Lip, Baby, Eyelid) and highlights its 'Irritant Free', 'Fragrance Free', 'Paraben Free', 'Dye Free', 'SLS Free', and 'Common Preservative Free' profile. Despite these favorable broad assessments, a specific in-depth review by regulatory bodies like CIR, SCCS, or FDA has not yet been identified for this precise derivative.
Your Skin
Skin Compatibility
Our Assessment
Verdict
Tetrasodium Disuccinoyl Cystine is a valuable ingredient for targeting hair and nail vitality, offering direct cellular energy enhancement and structural repair with a favorable safety profile.
Related
Similar Ingredients
Finding similar ingredients…