Last Updated: September 28 2022

Ascophyllum nodosum is a species of seaweed. It is being investigated for its immunostimulatory properties and it may inhibit carbohydrate absorption after supplementation.

Kelp is most often used for


Ascophyllum nodosum is a species of seaweed found around the globe. It is one of the many species of seaweed called kelp.

Ascophyllum nodosum contains compounds called phlorotannins, which are unique to seaweed and may be able to inhibit starch and lipid absorption. This effect is very unreliable, to the point where two human studies investigating carbohydrate absorption reported two opposite effects.

Ascophyllum nodosum also contains a compound called ascophyllan, which may have immunostimulatory properties. Ascophyllum nodosum extract has anti-inflammatory properties. Much more research is needed to determine the practical significance of Ascophyllum nodosum supplementation.

Though Ascophyllum nodosum is a healthy food, there is no evidence to support its usefulness as a supplement.

What else is Kelp known as?
Note that Kelp is also known as:
  • Kelp (one Of Many Species)
  • Egg Wrack
  • Rockweed
  • Ascophyllum Nodosum
Dosage information

Human studies investigating Ascophyllum nodosum use 4,600 mg of Ascophyllum nodosum extract added to a food product, taken once per day.

More research is needed to determine if this is the optimal dose of Ascophyllum nodosum. Different extract concentrates have not been tested.

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