Cysteine is an amino acid found in protein-rich foods like meat, poultry, fish, dairy, and eggs. It's also found in some plant foods but much smaller amounts. Cysteine is a building block of keratin, the protein that makes up your hair, skin, and nails. When you have a deficiency of this amino acid, it can lead to dry, brittle hair that is prone to breakage.
Cysteine Treatment For Hair is a way to replenish the levels of this amino acid in your hair and improve its condition. The treatment involves using a Cysteine-rich topical solution or serum applied to the hair.
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