Agar or agar-agar is a dry extract of red marine algae (seaweeds), which contains soluble fiber [1,2]. It is used as a food additive and supplement. Agar-agar in Malay means “jelly.”


Agar is a mixture of indigestible polysaccharides agarose and agaropectin, which are composed of galactose molecules, some of which contain sulfur [3].


Agar-agar is insoluble in cold but soluble in boiling water. When boiled, agar becomes liquid and when cooled it forms a clear, gel-like substance [1]. Agar’s melting temperature is 85-95 °C (185-203 °F) and gelling temperature (when cooled down) is 30-40 °C (86-104 °F) [3].


Agar-agar is indigestible, but large intestinal bacteria can break it down (ferment) to absorbable nutrients, mainly short-chain fatty acids (SCFAs), which can probably provide up to 2 kilocalories per gram [2].

Origin and Uses in Foods

Agar-agar is produced mainly in Japan, South America and Mediterranean countries.

Agar as a food additive is used as a thickener or “vegetable gelatin” or “vegetarian gelatin substitute.” It is used in pie fillings, meringues, ices, doughnut glaze, cream shells, sherbets, cream cheeses, canned and cured meats, sauces, noodles, baked products, soups, yogurts, cakes, ice creams, puddings, jelly candies and Japanese desserts, such as mitsumame and mizuyokan [1].

Agar powder and agar flakes are available in stores.

A Japanese word for agar is kanten. On the food products in the EU, agar is labeled with an E-number E406.

Agar Supplements

Agar is available over-the-counter as a soluble fiber supplement or bulk-forming laxative in the form of powder and capsules.

Possible Agar Health Benefits

There is INSUFFICIENT EVIDENCE about beneficial effects of agar on the following conditions [4].

  • In Japan, agar, as part of “kanten diet plan” is used to promote weight loss, since it supposedly has a satiating effect.
  • Agar capsules are sold as laxatives, because of its supposed bulk-forming properties.
  • Agar has been also used to lower blood cholesterol and glucose levels in individuals with diabetes mellitus.

Agar Safety and Side Effects

Agar, as a food additive is Generally Recognized as Safe (GRAS) by the US Food and Drug Administration (FDA) [5]. Agar may cause mild diarrhea and, theoretically, when ingested with insufficient fluid, esophageal or bowel obstruction [4]. Allergy to agar is possible.

Do not take agar if you have trouble swallowing or bowel obstruction or if you are pregnant. There is insufficient reliable information about safety of agar during pregnancy [4].

Agar vs Gelatin

Agar is a carbohydrate extracted from seaweeds, while gelatin is a protein obtained from animal bones.

Related dietary fiber:

5 Responses to "Agar-Agar"

  1. Kaye says:


    Thanks for the info, but can you answer my question – I have serious shellfish allergy. Do you think agar agar may cause allergy because it comes from the sea ?

    Please let me know so am sure before using it.


    • Jan Modric says:

      Being allergic to shellfish does not mean you will be allergic to everything “in the sea” despite the fact that there is a common cross-reactivity between shellfish and fish. I personally do not know why pure agar-agar, which is made of algae, would cause a reaction in someone who is allergic to shellfish. Note, that agar-agar can cause an allergic reaction in some people independently of shellfish allergy.

      The problem is that agar-agar comes as a specific commercial product, which may (or may not) include ingredients from fish or shellfish. This may be a reason why some websites recommend avoiding agar to those with shellfish allergies. You can find the info of such ingredients on the product label or on the producer’s website.

  2. Chan Richard says:

    Unfortunately I am also suffering from shelfish allergy which include chicken egg and peanuts. But I discover that by taking agar agar jelly in small amount seems to help.
    My allergy seems to be better and I also take chicken and egg without any discomfort.
    I think small amount of agar agar jelly does help.
    I stop taking it for about a month my skin allergy seem to come back.
    Maybe someone can help to explain this.

  3. Suresh bhatti says:

    Femal age 62, suffering with both knee pain.
    See some remady to use gelatin with pumpkinseeds,flexseeds,honey,sesam seeds.
    As we are vegetarian can i use agar agar powder instead of gelatin ?
    Can i get benifit by agar agar like gelatin ?.
    Please reply​ me soon.

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