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Ina Peters/Stocksy United Food: Seaweed, Wakame In A Bowl With Sesame

From plant-based chicken to fishless fish, it seems like there’s always something new cropping up in the world of sustainable food.

However, only some innovations in environmental eating are truly new.

Take seaweed, for instance.

While you may have enjoyed seaweed wrapped around your favorite fish in sushi, it hasn’t exactly become a household name in the west—yet.

However, seaweed farming may change that in the very near future. Read on to learn why seaweed might just be the next sustainable superfood.

This slippery algae from the ocean’s depths has been around forever, and may even be the world’s first plant.

When it comes to humans, 2020 research indicates that seaweed may have played a role in humanity’s evolution from Homo erectus to Homo sapiens as well as serving as a staple food in times of famine.

Evidence indicates that seaweed was used as food and medicine in Asia, Europe, and South America at least as far back as 14,000 years ago, and the Romans and Celts may have used seaweed to enrich infertile soil.

However, it isn’t just a rich global history that makes seaweed so interesting as a modern food crop. It offers a host of other benefits—from creating jobs to helping restore ecosystems.

According to Sachi Singh, founder of seaweed-based food supplement Rootless, “Seaweed could be the future of food.”

This is thanks in large part to seaweed aquaculture, also known as seaweed farming.

After spending a decade working on international climate and ocean solutions and earning a Master’s degree at the Yale School of Environment, Singh finally found what she was looking for.

“I always thought it was really interesting to contextualize and make personal a really complex global issue around food systems,” she says. “I kind of stumbled upon seaweed in this journey.”

For Singh, the nutritional, environmental, and social impact that seaweed could have was too big too ignore.

Growing seaweed systematically may be a viable solution to several challenges, from clean ocean water to economic stimulation.

Seaweed farming requires little to no resources

According to Jesse Baines, CMO of Atlantic Sea Farms, seaweed “is a zero input crop and actually leaves the ocean healthier with every harvest.”

Seaweed farming requires:

  • no arable land
  • no pesticides
  • no herbicides
  • no feed
  • no fresh water

According to Luke Gardner, PhD, is an aquaculture extension specialist at California Sea Grant. He says seaweed does most of the work necessary for its own cultivation.

Seaweed is “what’s called an ‘unfed’ aquaculture species, meaning that you don’t typically need to provide any additional nutrients for it to grow,” says Gardner. “It just uses the nutrients in the seawater.”

Seaweed farming supports healthy oceans

According to the National Oceanic and Atmospheric Administration (NOAA), the ocean absorbs about 30 percent of the carbon dioxide (CO2) that’s released in the atmosphere.

This leads to changes in ocean pH levels and increased acidity, negatively impacting fish, corals, and shellbuilders like oysters, crabs, and sea snails. These organisms are an important part of the ocean food web.

Luckily, seaweed captures carbon and nitrogen from ocean waters, leading to reduced ocean acidification. It also provides habitat to a number of ocean-dwelling organisms, helping to diversify ocean ecosystems.

“Our partner seaweed farmers are removing carbon and nitrogen from the local waters with every harvest and increasing biodiversity,” says Baines.

Seaweed farms:

  • reduce the amount of carbon in the ocean
  • reduce the acidity of ocean waters
  • provide habitat to ocean-dwelling species
  • diversify ocean ecosystems

Additionally, Gardner notes that seaweed farms may benefit more than just the ocean.

“​​There is some indication that seaweed farms may help to dampen wave energy and reduce erosion and other effects on shorelines,” he says.

Seaweed farming supports the economy

“Our waters are warming and fishing families are losing their livelihoods in the face of climate change,” says Baines. Seaweed farming creates “opportunities for fishing families to be more resilient in the face of climate change, while also mitigating some of its effects.”

Baines points out that almost all of the seaweed eaten in the U.S. is being imported, a missed opportunity for job creation and sustaining the existing fishing industry in the U.S.

“The U.S. imports almost all of its seaweed,” he says. “Atlantic Sea Farms is working to change that and ensure that consumers can find regenerative, domestically grown seaweed that prioritizes people and planet first in every aisle of the grocery store.”

When it comes to the health benefits of seaweed, the list of pretty long.


For starters, seaweed is known for being a great source of iodine.

It also has slight nutritional variations based on the type of seaweed.

For instance, kelp is a large, brown seaweed you’d find in shallow coastal fronts with nutrient-rich saltwater.

In 100g of raw kelp, you’ll find:

  • 55 percent of the daily value (DV) of vitamin K1
  • 45 percent of the DV of folate
  • 29 percent of the DV magnesium
  • 16 percent of the DV of iron
  • 13 percent of the DV of vitamin A
  • 13 percent of the DV of pantothenic acid
  • 13 percent of the DV of calcium

Note: DVs above are for the average male.

“Kelp is one of the most nutrient dense foods on the planet,” says Baines.

Wakame is a seaweed that’s been cultivated for centuries in Korea and Japan.

Two tablespoons, or 10 grams, of raw wakame contains:

  • 280 percent of the DV of iodine
  • 7 percent of the DV for manganese
  • 5 percent of the DV for folate
  • 4 percent of the DV for sodium
  • 3 percent of the DV for magnesium
  • 2 percent of the DV for calcium

Other types of seaweed include:

  • Nori, a red algae used to roll sushi that’s often sold in dried sheets.
  • Sea lettuce, a type of green nori often eaten raw in salads or cooked in soups.
  • Kombu, a type of kelp used to make soup stock or pickles.
  • Arame, a type of sweet kelp with a firm texture sometimes used in baking.
  • Dulse, a red algae used to add flavor to recipes and eaten as a snack.
  • Chlorella, a freshwater algae often used as a powdered supplement.
  • Agar and carrageenan, jelly-like substances used as plant-based binders and thickeners.

“There is some research that shows that seaweeds often have bioactive compounds that afford various different benefits,” says Gardner.

These compounds include:

  • antioxidants
  • polyphenols
  • sterols
  • alkaloids
  • flavonoids
  • tannins
  • proteins with essential amino-acids
  • polyunsaturated fatty acid

Medicinal uses

Seaweed has been found to have a number of medicinal qualities, including:

  • anticoagulant
  • antioxidant
  • antimicrobial
  • antiviral
  • neuroprotective
  • protective against cell damage

Several compounds in seaweed have been found to have therapeutic potential.

According to a 2021 study, some compounds in seaweed were found to be able to induce cancer cell death and anti-metastasis.

Though seaweed is a powerhouse when it comes to planetary and human health, there are a few things to keep in mind.

Too much iodine isn’t a good thing

Seaweed is a great source of iodine, but how much is too much?

According to a 2021 study, eating seaweed once or twice a week isn’t likely to be harmful. However, regular intake of iodine-rich seaweeds such as kelps could lead to excess iodine consumption.

Excessive iodine can negatively affect thyroid function, particularly in those with pre-existing thyroid disorders, pregnant people, and infants.

Farming repercussions

When it comes to seaweed farming, it may not all be positive.

“There are also some possible negative effects like increased number of farming gear in the water that could lead to things like whale entanglement and pollution from derelict or lost gear,” Gardner says.

Affordability and accessibility

While seaweed is affordable when purchased at Asian groceries, it may be on its way to becoming a high ticket item.

“Most of the seaweed sold [in the U.S.] is either from wild harvesting or small farms, with much of it heading to niche markets like high end restaurants,” says Gardner.

This could make U.S.-grown seaweed less accessible. On the other hand, imported seaweeds have their own downsides.

Some “are grown in compromised waters with questionable labor practices,’” says Baines.

They may also contain dyes, preservatives, and excessive sugar.

You can find seaweed at most grocery stores, but the best selection is often found at specialty or Asian groceries.

When it comes to Atlantic Sea Farms, there are a few places to look.

“We’re available nationally in the freezer section at Sprouts and refrigerated condiment section at Whole Foods,” says Baines. “We’re also in small independent grocery stores, fish markets, and food coops all over the country.”

Some brands sell their products online as well.

When it comes to eating seaweed, it may be a good idea to start with the old standbys.

“My introduction to seaweed was sushi and nori chips,” says Singh.

However, seaweed is incredibly versatile.

“You can literally add seaweed to anything!” says Baines.

He uses Atlantic Sea Farms Wild Blueberry Ginger Kelp Cubes in his daily smoothie for a burst of umami and antioxidants.

“I really enjoy ogo mixed into a poki dish or wakame used in soups,” says Gardner. “I find both to be really versatile ingredients in many dishes.”

Want to get adventurous with your seaweed consumption? Try these seven delicious recipes.

Singh’s favorite seaweed recipes

Seaweed butter

“I like to eat my seaweed butter with warm sourdough and a pinch of sea salt to bring out the umami,” says Singh. “I also like to fry my eggs in seaweed butter. Nutritious and delicious!”



  1. If using fresh seaweed, toast in a pan until aromatic.
  2. Grind the seaweed in a food processor, blender, or mortar and pestle until powdery.
  3. Mix the ground seaweed with the softened butter until blended completely.
  4. Wrap in plastic wrap or an airtight container.
  5. Store in the freezer for prolonged use or in the fridge for immediate consumption.

A seaweed-y take on a French 75:


  • 1 shot of seaweed Gray Whale gin (although any gin will do)
  • 2 tablespoons kombu simple syrup
  • 1 tablespoon lime juice
  • a few drops of saline solution
  • a few drops of toasted sesame oil


  1. Add all ingredients to a shaker with ice.
  2. Shake until blended.
  3. Top with sparkling wine.
  4. Enjoy!
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Have more questions about seaweed? Get the facts below.

Is seaweed a vegetable?

Yes, seaweed counts as a vegetable when it comes to nutrition. It’s chock-full of nutrients like iodine, vitamins, and minerals. Technically, seaweed is an alga, a type of sea vegetable.

How is seaweed used in food?

How isn’t seaweed used in food? It can be used for sushi wraps, to flavor soups and stews, and to thicken sweets and sauces. It’s also used in fertilizers, cosmetics, fuel, and animal feed.

What are the benefits of seaweed? Is dried seaweed healthy?

Seaweed is a nutrient-packed food that boasts significant amounts of iodine, folate, magnesium, iron, vitamin A, pantothenic acid, and calcium. Both dried and fresh seaweed offer these nutrient benefits.

Are there side effects to seaweed?

Seaweed is generally considered a healthy addition to a well-balanced diet. However, the high levels of iodine in seaweed can lead to thyroid issues, especially in those with pre-existing thyroid disorders, pregnant people, and infants.

Is it OK to eat seaweed every day?

Seaweed is rich in iodine, and excessive amounts of iodine can lead to thyroid issues. It’s recommended that consumers only eat seaweed once or twice a week.

How can you use seaweed in recipes?

Use seaweed as a wrap, a garnish, a salad ingredients, or a flavoring source. For more ideas, try these seven delicious recipes.

What is seaweed extract?

Seaweed extract is a biostimulant, also known as a fertilizer, extracted from seaweed. It’s often used to stimulate growth in plants, seeds, and crops.

So is seaweed the superfood of the future? It certainly has the potential to be.

Only time will tell if seaweed catches on as a zero-waste staple food crop that supports human and planetary well-being.

Crystal Hoshaw is a mother, writer, and longtime yoga practitioner. She has taught in private studios, gyms, and in one-on-one settings in Los Angeles, Thailand, and the San Francisco Bay Area. She shares mindful strategies for self-care through online courses at Simple Wild Free. You can find her on Instagram.