Ways to Eat More Foods With Seaweed—Plus All the Reasons You Should

Loaded with health benefits, seaweed can be a delicious addition to your diet.

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You've probably heard of raw seafood like sushi, crudo, or ceviche. But what about seaweed foods? The fact is, there are many ways to enjoy seaweed and even more reasons you'll want to. Here are the nutritional benefits of seaweed, the three types, and the safety precautions some people should take. Plus, learn how to incorporate more seaweed into your diet and how much to eat daily.

Health Benefits

Is seaweed good for you? The answer is a resounding yes. Not only does this sea algae have disease-fighting antioxidants and nutrients, but it has more of them than many vegetables grown on dry land.

"Seaweed is high in minerals and vitamins, including iodine, copper, calcium, magnesium, manganese, vitamin B2, and vitamin C," says Lisa Dreher, a registered dietician with the UltraWellness Center in Lenox, Massachusetts. "It's also one of the few food sources of the less well-known mineral vanadium. Preliminary research shows that vanadium may improve the body's sensitivity to insulin and decrease the body's production of glucose."

Moreover, Dreher notes that seaweed contains unique phytonutrients and antioxidants needed to protect cells and DNA against damage. "Plus, it favorably alters estrogen and phytoestrogen metabolism, meaning if eaten in moderate amounts over time, it can be protective in women at risk of estrogen-sensitive breast cancers," she says.

Types of Seaweed

There are countless species of marine plants and algae. "Seaweeds are categorized based on their coloring, cell structure, and other traits," says Tammy Lakatos Shames and Lyssie Lakatos, registered dieticians and founders of The Nutrition Twins. She explains that:

  • Red algae/seaweed is in nori and is the seaweed used in sushi.
  • Brown algae is known as seaweeds like kombu and kelp and is used in miso soup.
  • Green algae are found in sea lettuce and sea grapes.

According to Dreher, brown seaweed accumulates more iodine than other sea vegetables and can range from 110 to 1,500 micrograms of iodine per gram." But whether you eat nori, dulse, a blue-green alga like spirulina, or something else, every seaweed offers its unique nutritional perks, making them all worthy dietary additions for most people.

Who Should Avoid Seaweed

People With Hyperthyroidism

While seaweed is said to benefit people with hypothyroidism, it's not a great idea in abundance for people with hyperthyroidism. "Eating too many iodine-rich foods can worsen hyperthyroidism, so if you have it, you should avoid seaweed, as well as sushi rolls that are wrapped in seaweed," says Shames and Lakatos.

People on Blood Thinners

People on blood thinners might want to steer clear, too. "Check with your doctor before eating seaweed because it's rich in vitamin K, and blood thinners often work by interfering with the actions of vitamin K. Typically, if you increase the amount of vitamin K in your diet, you also need to increase your medication."

People With GI Upset

Dreher also notes that excess amounts of polysaccharides (carbohydrates) found in seaweed, which feed the bacteria in our gut, may contribute to gas, bloating, and gut discomfort in certain individuals, especially those with small intestinal bacterial overgrowth. "While the benefits outweigh the risks of eating seaweed in these situations, it's important to start with a small amount and then adjust based on how you feel."

The Safe Amount of Seaweed to Eat

For healthy individuals without a thyroid condition, the recommended daily allowance for adults 19 years and older is 150 micrograms, and the upper limit is 1,100 micrograms, according to Dreher.

Just be mindful of iodine content. "All seaweed varies as far as its iodine content. One dried sheet (1 gram) can contain anywhere from 11 to 1,989 percent of the RDA for iodine," she says. Dreher singles out the average iodine content of three common seaweeds to elucidate the disparity:

  • Nori contains 37 mcg of iodine per gram
  • Wakame contains 139 mcg of iodine per gram
  • Kombu contains 2,523 mcg of iodine per gram

Quality Matters

Dreher strongly recommends opting for organic seaweed from companies dedicated to producing products in clean waters, such as the Gulf of Maine and the North Atlantic.

"Seaweed can act like a sponge, easily absorbing heavy metals such as arsenic, lead, mercury, and cadmium," Dreher says. "Although trace amounts of arsenic are present in a lot of seaweed, these heavy metals can be much more concentrated in seaweed grown in water polluted by industrial waste as well as those that aren't organic."

Easy Ways to Add Seaweed to Your Diet

Mary's Gone Crackers and SeaSnax are the two most popular nutritionist-approved seaweed snacks, but you can also opt for miso soup packed with kombu (or seaweed flakes).

You can also add these flakes to roasted veggies and salads. (Many store-bought seaweed snacks are also very high in sodium, so be sure to check the labels.)

Another option is to add powdered spirulina, a type of seaweed rich in protein, to your favorite smoothie recipe, says Nealy Fischer, founder of The Flexible Chef.

Want to include seaweed as the main attraction? Here are a few quick meals that feature seaweed:

Seaweed Wraps

For those looking to cut carbs, take heed: "Seaweed wraps are also a great idea because they're basically a veggie-packed wrap without the carb-heavy exterior," says Fischer. "Start by simply julienning whatever veggies you have (think carrots, cucumber, mushrooms). Place them in a full-size nori sheet and roll everything like you would a wrap. Serve with a miso dressing for dipping."

Kelp Pad Thai

For something more filling, Fischer suggests raw kelp pad Thai. "Soak one package of kelp noodles in water until they become soft," she says. "Mix with your favorite pad Thai sauce until evenly coated. Serve with fresh cilantro, red pepper flakes, and other desired toppings."

You can bulk this dish up with your lean protein option of choice and unlimited non-starchy vegetables for a belly-filling, healthy meal.

Spring Fried Rice

One of the ingredients in this spring fried rice is nori, the dried seaweed often used to wrap sushi. Because of its umami properties, nori gives this dish a meaty, broth-like flavor.

Sauté the vegetables, rice, carrots, and a soy sauce mixture over medium-high heat. Stir in cashews and nori. Place in serving bowls and serve with fried eggs.

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