L glutathione soap (not to be confused with L glutathione pills), contains the skin lightening agent l glutathione, a compound that promotes cellular repair in the human body. It contains vitamin C and E, rosehip seed oil, and alpha lipoic acid, what soap maker Swiss calls the "universal antioxidant." Kojic acid originated in the Philippines, and developed more recently. It contains no vitamins, and its long-term effects aren't known as well as those as glutathione, and it's been known to irritate the skin with redness and peeling.

On the Other: Kojic acid

The active ingredient in papaya kojic soap is kojic acid. It's derived from a Japanese mushroom, and simulates the product of hydroquinone---a potent skin lightening chemical banned in the U.S, combined with extract of papain. Its effect is similar to glutathione, but according to its manufacturers, contains the added potency of kojic acid. L glutathione contains more natural and gentler ingredients.

Bottom Line

Kojic acid papaya soap contains the stronger ingredients; however, it is more likely to cause negative side effects such as skin irritation and sensitivity.

Source:

Skin-Whitening-Product: Papaya Kojic Acid Soap

Swiss: L Glutathione

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