L-fucose and fucose-rich polysaccharides increased elastic fiber density by about 40% in hairless rats after 4 weeks of topical application. In lab-grown human skin cells, these ingredients boosted tropoelastin (a building block of elastin) production by roughly 40%. The effect was specific to elastin—L-fucose actually decreased collagen production.

Researchers tested fucose on hairless rat skin for 4 weeks and separately added it to human skin cells in culture to measure elastin and collagen production.

Funding not disclosed in abstract