Ecklonia cava
Ecklonia cava


Ecklonia cava is a type of brown algae that is rich in phlorotannins, a type of antioxidant. It's used in food and medicine in Japan and Korea.

Ecklonia cava contains several chemicals that are thought to prevent damage to the body that can lead to cancer and other conditions. These chemicals might also have effects on swelling and the body's immune system.

People use Ecklonia cava for high cholesterol, cancer, osteoarthritis, athletic performance, diabetes, and many other conditions, but there is no good scientific evidence to support most of these uses.

Don't confuse Ecklonia cava with other types of algae, including Ascophyllum nodosum, Fucus vesiculosus, and Laminaria. These are not the same.
When taken by mouth: Most extracts of Ecklonia cava are possibly safe when used for up to 12 weeks. One specific extract (SeaPolynol) is possibly safe when used in doses of up to 263 mg daily.

Special Precautions & Warnings:

Pregnancy and breast-feeding: There isn't enough reliable information to know if it is safe to use Ecklonia cava when pregnant or breast-feeding. Stay on the safe side and avoid use.

Children: One specific extract (SeaPolynol) is possibly safe when taken by mouth in doses up to 163 mg daily in children aged 12-14 years, and 230 mg daily in children aged 14 years and older. There isn't enough reliable information to know if Ecklonia cava is safe for children under 12 years old.


NatMed Pro rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.
Likely effective Effectiveness definitions
Possibly effective Effectiveness definitions
  • High cholesterol. Taking Ecklonia cava extract by mouth might help reduce low-density lipoprotein (LDL or "bad") cholesterol in people with high cholesterol levels.
There is interest in using Ecklonia cava for a number of other purposes, but there isn't enough reliable information to say whether it might be helpful.
Likely ineffective Effectiveness definitions
Possibly ineffective Effectiveness definitions
Insufficient evidence Effectiveness definitions

Dosing & administration

Ecklonia cava extracts are often dosed by polyphenol content. The extracts are most often used by adults in doses of 144-400 mg of polyphenols daily by mouth for up to 12 weeks. Speak with a healthcare provider to find out what dose might be best for a specific condition.

Interactions with pharmaceuticals

It is not known if Ecklonia Cava interacts with any medicines. Before taking Ecklonia Cava, talk with your healthcare professional if you take any medications.

Interactions with herbs & supplements

There are no known interactions with herbs and supplements.

Interactions with foods

There are no known interactions with foods. has licensed monographs from TRC Healthcare.
This monograph was last reviewed on 30/03/2023 11:00:00. Monographs are reviewed and/or updated multiple times per month and at least once per year.
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