Carotenoids found in human skin include for example, lycopene, the carotenes, beta-cryptoxanthin, lutein, and zeaxanthin. These carotenoids protect the skin against sunlight damage. Lutein and zeaxanthin, which both absorb short-wavelength blue light, have been reported to reduce lipid peroxidation and to increase moisture levels and elasticity in the skin. With improvements in technology there is now the potential to non-invasively measure carotenoid status in the skin. Devices such as the Nu Skin Pharmanex S3 scanner measure total carotenoid concentrations using Raman Spectroscopy.
Work from the Nutrition Research Centre Ireland has shown that supplementation with the xanthosight formulation significantly improves skin carotenoid concentrations in addition to the benefits confirmed for the retina and brain.