By Hannah Sivak, PhD
Biochemist
Skin Actives Scientific

There is a consensus that hydroquinone can help with skin lightening of melasma and other types of hyperpigmentation, but the possible risks are significant. This is the time to replace hydroquinone with effective, safer actives

Kojic acid dipalmitate

Kojic acid is used in cosmetics for its excellent whitening effects.
Chemical modification of kojic acid using palmitic acid  increases its stability and decreases potential for skin irritation. Kojic acid is known for its non-problematic biodegradation, and is used in Japan in a variety of food and drink preparation methods.
Other properties: antifungal, chelates metals.

Brands that use kojic acid dipalmitate: Jan Marini Age Intervention; Dermaquest Skin Therapy Skin Vitalight. 
Note: Cosmelan 2 Maintenance depigmenting cream uses kojic acid (not modified), more unstable and irritating to the skin.


Arbutin (a.k.a. beta arbutin, ursine) is a chemical present in the leaves of the bearberry (Arctostaphylos uva-ursi) and responsible for the skin lightening properties of the plant extract.
It has a sugar group attached to one of the alcohol group of hydroquinone (HQ). Just like HQ, its shape resembles the amino acid tyrosine enough to ?fool? tyrosinase,  the enzyme that catalyzes the first transformation of tyrosine into melanin.
Inhibition of the enzyme in this way is called ?competitive? because the false substrate, arbutin, competes with the real one, tyrosine, for the active site of the enzyme.

Other properties: arbutin is also an antioxidant, alleviating oxidative stress responses such as leukocyte infiltration and hydrogen peroxide generation by chemical agents. 
Products that contain arbutin: Shiseido Whitess.


Melatonin


Secreted by the pineal gland in response to sunlight, it has been shown to decrease accumulation of melanin.

Other properties: Used in conjunction with magnesium ascorbyl phosphate (MAP), melatonin improved skin elasticity. It may also help with mouth sores (stomatitis), decrease the damage of radiotherapy on the skin and improve skin texture. Melatonin may help improve hair texture in female alopecia.


Magnesium ascorbyl phosphate suppresses cutaneous pigmentation.

Other properties: Once in the skin it will be transformed by skin enzymes into ascorbic acid, an antioxidant and a cofactor for an enzyme crucial in the synthesis of collagen (prolyl hydrolase). As an antioxidant agent, vitamin C scavenges and destroys reactive oxidizing agents and other free radicals. Because of this ability, it provides important protection against damage induced by UV radiation (and the DNA mutations and cancer that may result from it). Vitamin C also improves skin elasticity, decreases wrinkles by stimulating collagen synthesis, reduces erythema, promotes wound healing. Because body control mechanisms limit the amount of ingested vitamin C available to skin, topical antioxidant therapy becomes an efficient way to target the vitamin directly.


Products that contain magnesium ascorbyl phosphate: Shiseido UV White Control and Protect Base, Shiseido Revital Cream, ULTIMA II Vital Radiance Skin Renewing Toner, ~H2O+ Plus Waterwhite Brightening Tonic, La Prairie Cellular Intensive Anti-Wrinkle Anti-Spot Cream

Note: Cosmelan 1 Mask Intensive action depigmenting cream uses ascorbic acid (instead of the modified vitamin C), less stable and more irritating.

Liquorice (Glycyrrhiza glabra) extract: skin lightener
Other properties:  anti-inflammatory.


Products  that contain liquorice extract: Shiseido UV White Control and Protect Base, Shiseido White Lucency Concentrated Brightening Facial Serum, Cosme Decorte Whiteologist Sports Concentrate, Vichy Bi-White Reveal Double Corrective Whitening Essence, la prairie  Cellular Intensive Anti-Wrinkle Anti-Spot Cream

Tetrahydrocurcumin Skin lightener.

Purified curcuminoids from tumeric (Curcuma longa), strong yellow in color, are modified chemically to increase its biological availability and to turn them white.
Other properties: anti-oxidant, anti-inflammatory

Products that contain curcuminoids: Shiseido Revital Neck Zoom Essence, Shiseido Revital Wrinklelift Retino Science AA

L-Glutathione (gamma-L-Glutamyl-L-cysteinyl-glycine)
Is a tripeptide composed of the amino acids L-glutamine, L-cysteine and glycine.




Other properties: Glutathione is part of the antioxidant defense system of the cell, together with superoxide dismutase, catalase, alpha-D-tocopherol (vitamin E), ascorbic acid (vitamin C), etc. Glutathione is crucial to cell life, and impairment of the glutathione system results in damage to the cell membrane and cell death.


Vitamin E is an essential part of the cell antioxidant defense mechanisms.

Products that use vitamin E: Shiseido White Lucent Concentrated Brightening Facial Serum, Shiseido Whitess EX, Shiseido White Lucent Brightening Moisturizing Emulsion N

SOD + lactoperoxidase system comprises superoxide dismutase from horseradish and lactoperoxidase from bovine milk. This enzyme combination is included in the cream to disarm superoxide radicals, known to damage the skin and promote synthesis of melanin.