Back 20 years ago, you probably didn’t encounter seaweed too often unless you ate Asian cuisine or if your parents followed a macrobiotic diet. Fast forward to today and you can get multiple kinds of seaweed in virtually every grocery store across the country.

From Asia to New Zealand and even to Ireland, seaweed has been a nutritional staple in cultures for thousands of years. And now . . . it just might be your turn to start incorporating seaweed into your diet.

So what is seaweed anyway and is it as healthy as it’s cracked up to be?

Seaweed (known as sea vegetables and seagreens in other parts of the world) are a type of giant algae picking up a reputation as a superfood. Edible giant algae is very different from other forms of algae which can be either beneficial or toxic.

My friend from Japan was actually offended that in English, we refer to it as a “weed” since it’s so nutritious. We totally get it! We feel the same way about dandelions being called weeds when we do everything from add them to salads to make our dandelion citrus lotion bars . . . You may recognize seaweed from Japanese restaurants, from the paper-like wrapping around sushi, floating on top of miso soup or seaweed salad, but sea vegetables are starting to make a big splash in American menus too. And for good reason.

The Health Benefits of Seaweed

Seaweed is packed with fiber and minerals such as iodine. Research suggests that certain sea vegetables have powerful health benefits, including targeted anti-cancer properties that killed cancer cells but left healthy cells alone. Researchers who have been studying the effect of certain sea vegetables (wakame and mekabu) on breast cancer found that,

“These effects were stronger than those of a chemotherapeutic agent widely used to treat human breast cancer. Furthermore, no apoptosis induction was observed in normal human mammary cells. In Japan, mekabu is widely consumed as a safe, inexpensive food. Our results suggest that mekabu has potential for chemoprevention of human breast cancer.”

The research review “Seaweed and Human Health” found that “seaweeds may have an important role in modulating chronic disease.” 

“Rich in unique bioactive compounds not present in terrestrial food sources, including different proteins (lectins, phycobiliproteins, peptides, and amino acids), polyphenols, and polysaccharides, seaweeds are a novel source of compounds with potential to be exploited in human health applications. Purported benefits include antiviral, anticancer, and anticoagulant properties as well as the ability to modulate gut health and risk factors for obesity and diabetes.”

In other words, since seaweed grows in a completely different from vegetables that grow in soil, it contains unique properties that we're just beginning to discover. From its fiber that may be beneficial to for human digestion to iodine and mineral content supporting thyroid function, it's worth considering making it a regular part of your meals.

But before you rush out and fill your shopping cart with seaweed, there’s one thing to be aware of. . . heavy metals.

But. . . what about heavy metals? Is seaweed safe to eat?

Seaweed can act like a sponge for minerals in ocean water. For healthy minerals such as iodine, that’s a nutritional bonus. Unfortunately, algae can absorb heavy metals (particularly in polluted waters). 

According to WFFoods.org:

“Among all of the heavy metals, arsenic appears to be most problematic when it comes to sea vegetable toxicity risk. Virtually all types of sea vegetables have been determined to contain traces of arsenic. These types include arame, hijiki, kombu, nori, and wakame. Among all types of sea vegetable, however, hijiki stands out as being particularly high-risk when it comes to arsenic exposure.”

Even the Australian government did some digging on whether seaweed was safe to eat due to inorganic arsenic levels and they came to the conclusion that with the exception of hijiki, seaweed products met safety standards. You can avoid most of the heavy metal concern by purchasing farmed sea vegetables, which are closely monitored or even have controlled water environments but it may be a good idea to avoid hijiki until an organic farmed source becomes available. Because of the arsenic risk, we’ve left it off of our list of seaweeds to try. Until there's an organically farmed source of hijiki, you can think of it as the Metallica of the ocean. . .🤣

And speaking of farming, that brings us to another benefit of eating sea vegetables. . . sustainable aquaculture.

Sustainability Seaweed Farming

Although seaweed is a fast-growing plant (giant kelp can grow 12 – 24 inches per day), pollution and over-harvesting in the wild is a key consideration as edible seaweed grows in popularity. Responsible aquaculture, ocean farming, is a way for seaweed to be sustainable and renewable as well as ensuring that the crops are monitored for safety.

9 Types of Sea Vegetables to Try

So how do you actually start eating seaweed and have it taste good? Good question, even if you didn't ask it, my friend. An easy way to get started is to incorporate what I call the 4 S approach.

• Salads
• Stir-fries
• Soups
• Snacks

1. Arame. This brown seaweed is part of the kelp family and looks like long grass. It's often used in stir-fries and soups and pairs well with mushrooms.
2. Agar. This fiber is made from a variety of red algaes and is used in Asian desserts as a thickener. It can be purchased at an Asian grocery store (or Amazon) and used as vegan gelatin.
3. Dulse. While dulse normally tastes like the ocean, Bon Appetit Magazine has discovered that pan-fried fresh dulse tastes like – are you ready for this – bacon. Expect to see more of this ingredient in restaurants and even in products on the shelves very soon.
4. Green seaweed/sea lettuce. This is a popular form of seaweed for foragers and harvesters as it can be eaten raw or lightly dehydrated.
5. Irish Moss/Sea Moss. While carrageenan (a thickener used in commercial food products) is derived from Irish Moss and may be harmful to health, whole Irish Moss is not the same thing. Sea moss is often used as an ingredient in smoothies, soups, or sauces and is not eaten on its own.
6. Kelp. We think of kelp as the king of seaweed! A favorite of ours is kelp noodles (sold on the shelf or in the refrigerated section of your local health food store), which are low carb, crunchy, and the perfect vehicle for a delicious sauce. We toss kelp noodles with shredded carrots, tamari, lime juice, and sesame oil for a perfect chilled salad.
7. Kombu. Kombu is used as a flavoring to give that umami flavor to soups and stocks. Add a 2-6″ strip of dried kombu to simmering soups to add a meaty flavor without meat.
8. Nori/Laver. Popular with kids, this seaweed is rolled into sheets and toasted and is what you may be used to seeing on the shelves of the grocery store. Nori is commonly used to wrap sushi and is now a flavored snack that kids love. This is a staple in our household and even though sometimes the kids are too shy to bring it out of their lunchboxes, they eat them 2-3 packages at a time at home. You can get these as mini packages of toasted snacks at your local grocery store, Costco, or Amazon.
9. Wakame. Closely related to kombu, this variety is a form of kelp that's versatile in cooking and fun to eat in seaweed salads. 

My favorite way to include sea vegetables in my family's diet is using kelp noodles to make a chilled Asian salad. Seagreens are low carb, packed with fiber and minerals, and suited for most diets – including gluten-free, vegan, paleo, and keto. On a low carb or keto diet? Nori snacks are a perfect chip replacement for when you're craving something salty.

Seaweed. It’s what’s for dinner.

Looking for a way to get started swapping out a few vegetables for seagreens in your cooking? Check out these cookbooks for a little inspiration on your seaweed cooking adventure. These recipes focus on simple swaps with vegetables you're already familiar with. 

And. . . are you a seaweed fan? Let us know your favorite way to eat seaweed in the comments!