What is Seaweed?

Seaweed is marine macro-algae. Other types of algae include marine micro-algae, such as phytoplankton, and freshwater algae (chlorella, spirulina), some of which are also edible. While they share similarities, seaweed is not a plant in the scientific sense of the word, and pre-dates the existence of terrestrial plants by 700 million years according to the fossil record. Seaweed is both the first known multi-cellular organism on the planet, and the first organism known to reproduce sexually.

Terrestrial plants and seaweed both create food for themselves through photo-synthesis, but rather than absorb minerals and nutrients from the soil as plants do, seaweed absorbs trace minerals directly from the ocean water. Unlike terrestrial plants, seaweed does not require a vascular system to transport nutrients throughout the organism, being immersed in an ocean of nutrients fully available to the entirety of the organism.

Seaweed has a holdfast in place of roots, a stipe instead of a stem, and fronds in lieu of leaves. The holdfast serves strictly as an anchor, and does not absorb nutrients from the substrate to which the seaweed is attached. Seaweeds reproduce by spore, and belong to the scientific kingdom of eukaryotic organisms known as "Protista," whose primary membership requirement is that you are neither a plant, animal, or fungi.

Why is seaweed so nutritious?

Seaweeds contain more Vitamin C than oranges, more Calcium than milk, more Iron than spinach and beef. Seaweed concentrates the naturally occurring trace minerals in ocean water and makes them available to us in dietary form. There are 66 trace minerals in seawater, and seaweed contains all of them. Trace minerals promote healthy thyroid function, prevent cellular damage, strengthen the immune system, and aid in brain development.

Seaweeds are also...

-The best dietary source of iodine

-High in anti-oxidants

-High in Omega-3 Fatty Acids

-Rich in a broad spectrum of vitamins

-A source of beneficial compounds found nowhere else in nature, including Laminarin, Fucoidan, and Algin.
These unique compounds have been found to sooth the gastrointestinal tract, aid in removing heavy metals from the body, and prevent carcinogens from being absorbed by the digestive system.

The American Thyroid Association estimates that more than 12 percent of the U.S. population will develop a thyroid condition during their lifetime, and approximately 40% of the world’s population remains at risk for iodine deficiency.

Women are five to eight times more likely than men to have thyroid problems, and one woman in eight will develop a thyroid disorder during her lifetime.



Are all seaweeds edible?

Almost all seaweeds are technically edible, but many are not palatable enough to be considered food. There are approximately 10,000 known species of seaweed around the world, and about 250 in the Gulf of Maine.

Only a handful of seaweeds in the North Atlantic are considered toxic, all in the genus Desmarestia, commonly known as “sour weed.” They contain sulfuric acid, and are unpalatably sour. If removed from the water and placed in a warm environment, they release the sulfuric acid stored within their fronds and are “cooked” alive in their own juices. It is theoretically possible to eat enough Desmarestia to give yourself a stomach ache, but to the best of our knowledge no one has tried.

What’s the difference between Seaweed and Sea Vegetables?

"Sea Vegetable" is an informal umbrella term for the varieties of seaweed commonly used for culinary purposes. One well-known definition of a "weed" is "A plant whose virtues have not yet been discovered." (Ralph Waldo Emerson)

Is Seaweed harvesting regulated?

Seaweed harvesting is regulated by the Maine Department of Marine Resources, and a license is required to harvest any amount for commercial purposes. Harvesters must report when, where, and how much they harvest, along with the techniques used to harvest, and the end-use of the seaweed. An individual may collect up to 50 wet pounds a day for personal use without a license. Informal boundaries and territories also exist among commercial harvesters to prevent over-harvest.

Is Kelp different from other types of seaweed?

Seaweed is divided into families by color. There are brown (phaeophyta), red (rhodophyta), and green (chlorophyta). Kelp/Kombu is a sub-family of brown seaweeds, and the name is sometimes used to refer to other species of seaweed for marketing purposes that are not true kelps, such as Ascophyllum.

Up to 95% of the seaweed harvested in Maine in a given year is "rockweed" (Ascophyllum nodosum), which is primarily used as food for plants and animals.

How long have people been eating seaweed?

There are written records in China of seaweed being used as food and medicine dating to 5,000 years ago, poems in Northern Europe describing Icelandic monks harvesting dulse dating to the 13th century, and records of seaweed being accepted as payment of taxes in 6th Century Japan.

The oldest archeological record of seaweed consumption dates to 14,000 years ago in Chile, South America, where the remains of stone cooking tools contained residues of 20 different species of seaweed at a campsite 40 miles from the ocean. One of these species was a type of Porphyra, the variety of seaweed used to make Nori sheets for sushi.