Hidden in Plain Sight

Without realizing it, you likely ate or used products that contain seaweed today. That is because algin and carrageenan — two common additives — come from seaweed.

We add seaweed to products to:

  • thicken them
  • transform them into gels
  • keep their ingredients from separating

Good to Know . . .

Ball of green, pink, and pale-yellow Irish Moss leaves on a grey wooden surface.

Acadian Seaplants

Hand raising a rope covered in long, brown kelp leaves out of the water.

Cascadia Seaweed

Algin comes from brown seaweeds such as kelp, while carrageenan comes from red seaweeds such as Irish moss.


Salad dressing, chocolate milk, almond milk, pet food, toothpaste, shampoo, lipstick, cosmetic creams, paint, and many other familiar products are thickened with seaweed.

That is because both algin and carrageenan can absorb large quantities of liquid. Add them to a product, and they will affect its thickness and texture.

Chocolate milk pouring from a glass bottle into a drinking glass.


For example, carrageenan gives chocolate milk its velvety texture.

Worker applying yellow paint to a silkscreen printing frame, with another worker drying printed shirts in the background.


Half of the world’s algin is used by the textile industry. When added to dye, algin prevents colours from bleeding, which results in a clearer print.

Open cans of paint in different colours, each with a plastic spreading tool in the can.


Algin gives paint a thicker texture, which stops it from running when applied.

Open glass jar of pink beauty cream with metal lid leaning against it.

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Many personal care products — such as toothpaste, shampoo, lipstick, and cosmetic creams — get their thick texture from either algin or carrageenan.

Transforming into Gels

Lipstick, cosmetic creams, face masks, soft gel capsules, heartburn medication, throat lozenges, air fresheners, shoe polish, pet food, chicken nuggets, ice cream, and many other food and home products get their gelled texture from seaweed.

Breaded chicken nuggets on a wooden board, garnished with parsley, beside two pots of dip.


The gels formed from carrageenan tend to be firm, and will not melt when heated. This makes them ideal for foods that need to hold their shape when cooked, such as chicken nuggets.

Gel air freshener with white plastic shell open, showing the lime-green gel inside.

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Gels from algin are more flexible. This gives them a gravy-like texture, which is ideal for products such as dog food. Some algin gels will even melt slowly at room temperature, allowing them to release their ingredients, as in solid gel air fresheners.

Groups of yellow, red, and green gel capsules against a white background.


Medications that contain algin help relieve heartburn by forming a gel that keeps stomach contents from travelling up the throat.

Some types of throat lozenges contain algin. When swallowed, the algin gel coats and soothes the throat.

Red lipstick in a black tube with the cap removed.

Yellow Cat/Shutterstock

When algin is used in lipstick, it forms a gel over the lips, which helps to keep the colour from rubbing off.

Keeps Ingredients from Separating

Seaweed keeps the ingredients in salad dressing, paint, infant formula, toothpaste, almond milk, and ice cream from separating.

Variety of unlabelled clear plastic bottles, each containing a different type of creamy or oil-based salad dressing.

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Algin and carrageenan can be used in salad dressings to keep ingredients such as vinegar, oil, and spices from separating.

Rows of open ice cream cartons, each with a different colour and texture.


Algin makes ice cream smoother. It helps to stop ice crystals from forming during freezing, which would give ice cream a rough texture.

Wooden bowl containing sour cream and a wooden spoon, placed on a loosely bunched grey tea towel on a stone surface.


In dairy products, such as ice cream and chocolate milk, carrageenan keeps milk components, such as fat and protein, from separating. It does the same thing in almond milk and infant formula.

Mint-green toothpaste being squeezed out onto a manual toothbrush.

Africa Studio/Shutterstock

Algin stops water and abrasives from separating in toothpaste.