What it is
This extract is derived from Macrocystis pyrifera, one of the largest species of brown seaweed, and is valued in cosmetics for its content of polysaccharides, minerals, and other water-soluble components. In sunscreens it is generally used as a conditioning and moisture-supporting botanical that gives the formula a marine or naturally derived positioning. It is incorporated into the water phase and used at low levels.
Safety & warnings
Marine and seaweed extracts of this type are generally well tolerated topically and are not commonly associated with irritation at cosmetic use levels. They are water-soluble and not considered comedogenic. As with other botanical extracts, sensitivity is possible in rare individuals.
Origin & sourcing
It is a natural marine ingredient obtained by extracting harvested giant kelp, a brown alga that grows in cold coastal waters; the extract is typically standardized and preserved for cosmetic use.
Questions everyone asks
What is giant kelp extract used for in sunscreen?
It is used as a conditioning and humectant botanical, contributing polysaccharides and minerals that support a moisturized skin feel.
Is this ingredient a UV filter?
No. It is a marine botanical used for skin conditioning, not for absorbing or reflecting UV light.