Algin
Sodium salt of alginic acid from brown algae (laminaria, ascophyllum). A natural thickener and film former – it builds a gel and holds water. Common in masks, gels, and foundations. Low allergenicity and pregnancy-safe.
Supporting ingredient
It gives a product its texture, stability or shelf life. It has no claimed effect on the skin, so an efficacy tier does not apply. What is known about its safety is below
Tolerability and safety
- Irritation potential
- Low
- Allergen risk
- Low
- Pregnancy
- Safe
- Suitable for
- Normal, Dry, Combination, Oily, Sensitive
About this ingredient
Algin (sodium alginate) is a natural polysaccharide extracted from the cell walls of brown algae of the Laminaria, Macrocystis, and Ascophyllum genera. It consists of D-mannuronic and L-guluronic acid residues linked into linear chains. The molecular weight of commercial alginate ranges from 50 to 1000 kDa depending on use. INCI: Algin. Alternative names are Sodium Alginate and Algae Extract (when not purified). In cosmetics, alginate works as a thickener and film former. On contact with divalent cations (calcium) it turns into an elastic gel – the principle behind alginate masks, which are applied as a liquid paste and peeled off as a single sheet after 10-15 minutes. In standard creams and serums alginate at 0.1-1% gives a pleasant slip, holds water on the skin, and stabilizes other actives. INCI E401 in food. Pregnancy safety. Topical use is safe. Systemic absorption is absent – the molecule is too large. Alginate is also used in medicine: alginate wound dressings and antireflux preparations like Gaviscon. Skin tolerance. Low irritation and allergen potential. Suitable for sensitive and pediatric skin. Safe during pregnancy and lactation. What not to expect. Alginate has no standalone anti-aging or brightening activity. Marketing claims of cellular renewal or lifting through an alginate film are not supported by clinical studies. The positive effect of alginate masks is occlusion and temporary hydration, not cellular regeneration. It is a reliable functional polysaccharide with very good tolerance.
Frequently asked questions
Is Algin safe during pregnancy?
Algin is considered safe during pregnancy at typical cosmetic concentrations. Systemic absorption through the skin is minimal.
What skin types is Algin for?
Algin suits: normal, dry, combination, oily, sensitive.
What is Algin and what does it do in cosmetics?
Sodium salt of alginic acid from brown algae (laminaria, ascophyllum).
Is Algin comedogenic?
On the Fulton scale 0/5 – non-comedogenic. For acne-prone skin, a rating of 3 or higher suggests choosing an alternative.
What's the INCI name for Algin?
The INCI name is Algin. It may also appear as: Sodium Alginate.
See Algin in a product composition right on the store page
The Evigrade extension adds an evidence panel to iHerb, Sephora, Druni and 12 more stores. This ingredient and every other one in the product show evidence-tier, allergen risk and pregnancy/lactation flags at a glance.
Similar role in the formula
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