L-cysteine, or cysteine, is a non-essential amino acid found in a variety of foods and naturally in the structure of the hair, skin, and nails (J. Applied Cosmetology, 2012). Like all amino acids, the real value of cysteine comes from its assimilation into the protein. The bloodstream absorbs amino acids and deliver them to all of the key tissues of the body, including the skin, hair, and nails, where they are assimilated into structural proteins like collagen, elastin, fibrin, and keratin.
A Natural Hair and Nail Growth Supporter
L-cysteine in particular is regarded in the hair and nails as a revitalizing agent, stimulating the growth of both the hair and the nails in a statistically-significant manner, and enhancing anti-static resistance of the hair (J. Applied Cosmetology, 2012).
Excellent for Treating Age Spots and Providing Antioxidant Protection For the Skin
When cysteine is the form that can be utilized readily by the skin, it is called L-cysteine. [Read more: What is the Difference Between an L-Amino Acid and a Non-L-Amino Acid?] L-cysteine has been shown to inhibit the production of melanin (skin pigment) in at least one study (J. Applied Cosmetology, 2012). In the study, L-cysteine was showed to inhibit the action of tyrosinase, an enzyme required for skin pigment to form. This suggests that L-cysteine may prevent or reduce the appearance of age spots, melasma, and other signs of hyperpigmentation.
Another way L-cysteine may fight hyperpigmentation is by promoting circulation. As you may know, some dark undereye circles are generated from the accumulation of blood cells in the area. In one study, L-cysteine was added to a test solution with red blood cells; another control sample added a cysteine-free solution to the red blood cells. The solution was incubated for 10 minutes. The cells were shown to increase the breakdown of the red blood cells, indicating that L-cysteine may promote the breakdown of hyperpigmentation caused by unwanted bruising and blood accumulation as well.
As L-cysteine, the amino acid may also play a critical role in antioxidant defenses, and has involvement in many biological pathways (Nutrition, 2012):
- Glutathione, which is a prominent antioxidant naturally found in nearly all cells of the body. Glutathione deficiency is associated with aging, liver disease, cystic fibrosis, sickle cell anemia, stroke, and diabetes (Nutrition, 2012). Glutathione is comprised of amino acids glutamate, glycine, and cysteine; a depletion of any of the amino acids, including cysteine, will result in a depletion of glutathione.
- Keratin, the structural protein of the hair, is also comprised partially of cysteine.
- Cysteine supplementation has been associated with aided recovery of inflammatory bowel disease, sepsis, burns, and post-intensive care stress (Nutrition, 2012).
- Cysteine is a natural source of sulfur, which is a natural anti-acne agent (CMAJ, 1965).
A Natural Skin Booster
As with all amino acids, cysteine is naturally found in the skin at higher concentrations when you are younger. As the years go by, your body’s processes slow and some stop entirely. The result? You need to supplement the amino acids your skin is no longer making in order to maintain the same rate of essential proteins for your skin!
Studies show that cysteine may be vital in maintaining strong, healthy, non-oily, less-pigmented skin. L-cysteine has been shown to boost UVA/UVB protection in at least one study (Journal of Photochemistry and Photobiology, 2003).
Skin care with the amino acid cysteine should provide your skin with more structure and firmness, as your skin is getting the resources it needs to boost keratin, collagen, elastin, and other structural proteins.
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