Astaxanthin is the red carotenoid pigment produced by the microalga Haematococcus pluvialis when it is stressed — and the reason salmon, krill and flamingos are pink, since it accumulates up the food chain. In skincare it is prized as one of the most potent naturally occurring antioxidants measured.
How it works
Its long conjugated molecular backbone lets it quench singlet oxygen — a particularly damaging reactive species generated in skin by UV exposure — with an efficiency many times that of vitamin E in comparative laboratory assays. Unusually for an antioxidant, the molecule spans the full width of a cell membrane, polar ends anchored at both surfaces, so it can intercept radicals at the membrane’s edge and in its oily core at once.
Published topical research has associated astaxanthin with support for skin elasticity and moisture and a reduced inflammatory response after UV exposure — consistent with its role as a photo-stress defence molecule in the alga that makes it.
In formulation
Used at low percentages — its deep red colour tints a formula visibly, which practically caps the dose. It appears in antioxidant serums alongside vitamins C and E, where the network of antioxidants regenerates one another. Non-exfoliating, non-photosensitising and well tolerated.
It is an antioxidant support, not a sunscreen — daily SPF remains the actual photoprotection.
