Used as an emulsifier and emollient. Soy extract is a potent antioxidant and anti-inflammatory agent for skin. Soy is one of many phytochemicals that are biologically active against free radicals. Soy extract’s increasing use in anti-aging products is largely due to studies showing that its antioxidant genistein (a component of soy) has a collagen-stimulating effect and that various compounds in soy influence skin thickness and elasticity.
Researchers have also looked at Bifidobacterium-fermented soy milk extracts. On mouse skin and in human skin fibroblasts (lab cultured), this bacteria-modified form of soy was shown to stimulate the production of hyaluronic acid in skin. This was due to the amount of genistein released during the fermentation process.
Soy extract has been shown to help reduce the effects of UVB exposure on human skin cells. Soy has also been found to have anti-androgenic effects.
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