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Algin

What Algin is & what it does

Algin, also known as sodium alginate, is a polysaccharide derived from brown seaweed. In skincare and sunscreen formulas it works mainly as a thickener, film former, and gelling agent that helps stabilize the texture and improve how a product spreads. A notable property is its strong gel-forming ability, which is why alginates are also widely used in peel-off and rubber-style masks.

What does Algin do in skincare?

Algin, also called sodium alginate, is a seaweed-derived polysaccharide used in skincare and sunscreen as a thickener and gelling agent. It helps stabilize the texture of a formula and improve how it spreads. Its strong gel-forming ability also makes it a common base for peel-off and rubber-style masks.

Is Algin natural or synthetic?

Algin is a naturally derived ingredient, extracted from brown seaweed. It is a plant-based polysaccharide rather than a lab-synthesized polymer. This natural origin is one reason it is popular in seaweed-themed and naturally positioned products.

Is Algin safe?

Algin is widely used in cosmetics and also in food, and is generally considered safe and well tolerated. As a large, seaweed-derived molecule it tends to stay on the skin surface rather than penetrate. Individual sensitivities are possible but uncommon for this type of ingredient.

Sunscreens with Algin

We rate 51 sunscreens that contain it, showing the top 10 by overall score:

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