More commonly known as tamarind, the seed extract is used more often for care of the eye itself rather than for skin care. According to Natural Medicines Comprehensive Database. "Tamarind seeds contain a polysaccharide with a branched chain structure similar to the mucin found in the eye, which helps protect and wet the corneal surface. Eye drops containing this polysaccharide are being studied in dry eye syndromes."
When it comes to skin care, newer research has shown that, at least in the lab, tamarind has an effect on skin cell proliferation, including the proliferation of fibroblasts, which are the cells that build skin's chief supportive element, collagen. Thus, tamarind seed extract and its related plant sugars seem to function as cell-communicating ingredients (Source: Dermatology Research and Practice, ePublication, September 2013). Other research suggests tamarind seed offers some protection against UV damage (Source: Journal of Cosmetic Science, March-April 2012, pages 119-131).