Seaweed Is the Next Trendy Superfood

There's now a growing appreciation for this marine delicacy due its potential health benefits, versatility and sustainability. Have you tried adding it to your meals?

STORY AT-A-GLANCE

• Westerners are catching up and taking notice of kelp, hailing it as the next superfood

• Fucoidans, a powerful polysaccharide found in kelp and some types of seaweed, has been identified to provide anti-aging and immune-boosting effects

• The potent antiviral properties of seaweeds were also proven by several studies. One study found that seaweed may inhibit herpes simplex virus types 1 and 2, with very low toxicity to other cells

• You can consume kelp and most varieties of seaweed raw, cooked and added into foods or served as a side dish or salad, or chopped in bits and added as a topping to your meals

• Be mindful of your portions though, as most seaweeds contain polyunsaturated fatty acids (PUFAs), including linoleic acid, which is harmful to your health in excessive amounts. Limit your LA consumption to 5 grams, or even better, 2 grams a day to protect your health

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In Asian households, seaweed is an integral part of daily meals. It’s added to soups, used as a salad ingredient, served as a side dish, and even dried and eaten as a crunchy snack. In Japan, around 21 types of seaweed are used in cooking, six of which have been used as far back as the 8th century.¹

Seaweed isn’t just versatile and delicious, but healthy as well. And the good news is Westerners are catching up and taking notice of this marine delicacy, hailing it as the next superfood.

Seaweed Is Gaining Traction as the Next Superfood

Data from the market research firm Mintel said that kelp seaweed could be the next rising superfood. According to a Food Navigator article,² the firm’s data, which was acquired through their Ingredientscape AI tool, found that the prevalence of kelp seaweed in new products across Europe increased from 2005 to 2023, and they "expect the number of product launches containing kelp seaweed to grow further in the coming year."

Emma Schofield, associate director of Global Food Science at Mintel, says that the health and sustainability benefits that kelp seaweed offers are the primary reasons why there’s a growing interest in algae today. In the Food Navigator article, she comments:

"Seaweed has already gained popularity in western cuisine as chefs and food manufacturers explore its unique flavors and nutritional value. Food and drink brands have the potential to explore greater options with kelp.

For example, in the snack category, creating seaweed-infused crispy seaweed chips or mixing seaweed into already popular items such as crackers or popcorn. Manufacturers can make seaweed more approachable for consumers and enhance its adoption by presenting it in familiar formats."

Schofield also mentions that the growing interest in kelp may prompt European food manufacturers to change how they source their products. Instead of relying on seaweed imports from countries like China and Korea, Europeans may consider developing the market for locally produced seaweed.³

Kelp and Other Seaweeds Are Abundant in Nutrients

Kelp is a variety of seaweed that grows in vast seabeds in coastal regions all over the world. It’s also called brown algae (phaeophyta⁴), and thrives mostly in cold, nutrient-rich waters.⁵ According to the World Resources Institute:⁶

"Commonly described as a foundation species, kelp creates forest-like habitats fostering huge and diverse amounts of life, including sea snails, brittle stars, lobsters, various species of fish, seals, sea otters and more.

Kelp forests are found along 25% to 30% of the world’s coastlines, making them the most extensive marine-vegetated ecosystems in the world. They are predominantly cool water species and can be found in temperate, Arctic and sub-Antarctic areas. Some of the largest forests are located along the California and Pacific Northwest coastlines, up to and including Canada and Alaska."

Kelp has been dubbed a marine superfood, and Food Navigator reports that its potential health benefits will potentially "attract the interest of wellness-minded consumers," prompting the food industry to incorporate it into their products.⁷

Indeed, kelp and other types of seaweed — nori, kombu and wakame, to name a few — are nutritionally diverse, offering a wide array of nutrients that can provide whole-body benefits. According to a report in the journal Marine Drugs, seaweeds offer:⁸

• Vitamins A, C, D, E and K

• Essential minerals like calcium, iron, iodine, magnesium, phosphorus, potassium, zinc, copper, manganese and selenium

• B vitamins (B1, B2, B9 and B12)

• Protein and essential amino acids

• Anti-inflammatory polyphenols

• Dietary fiber

Seaweed is also rich in arginine, glycine, alanine and glutamic acid, and contains all the essential amino acids. It has dietary fiber, which is essential for digestive health.⁹ The iron in seaweed helps with healthy blood formation and may prevent anemia, while the polyphenols help fight free radicals. These functions help ensure the growth of strong bones and optimal muscle function.

"Consumption of kelp seaweed has been linked to the improvement of sensory receptors, promoting healthy blood vessels, aiding in digestion and weight management and even reducing hair loss," Food Navigator¹⁰ reports. Just be mindful of your portions if you already have high iron levels.

Seaweed Plays a Role in the Lives of Japanese Centenarians

Japan has one of the highest centenarian populations, with 92,139 people recorded as of September 2023.¹¹ Most of them live in Okinawa, an island that’s been dubbed as a "Blue Zone" of longevity.¹²

While many factors contribute to their long lives, such as being stress-free and appreciating day-to-day pleasures, one specific aspect that’s been considered is their nourishing diet composed of farm-to-table ingredients, with seaweed as one of the foundational components.¹³

In particular, fucoidans, a powerful polysaccharide found in some types of seaweed including kelp, has been identified to provide anti-aging and immune-boosting effects.¹⁴ Fucoidans make up 25% to 30% of seaweed’s dry weight, depending on the type and the season. According to a study in Marine Drugs, they present biological activities such as:¹⁵

• Antibacterial

• Antiviral

• Anti-inflammatory

• Anticoagulant

• Antithrombotic

• Antidiabetic

• Procoagulant

• Anticancer

An article published in FoodTrients¹⁶ further expounds on the longevity-promoting benefits of fucoidans, stating that:

"It has been shown that fucoidan-rich Undaria, once ingested, can bind to toxins such as dioxin within the mammalian body and facilitate its excretion.¹⁷ The effect is noteworthy enough that some clinicians believe it could hold promise as a therapeutic intervention in humans exposed to dioxin.

Laboratory and animal studies further reveal that fucoidans prevent certain infectious diseases, and block cancer cells from spreading and trigger their early death.¹⁸"

Seaweeds May Have Potent Antiviral Capabilities

The potent antiviral properties of seaweeds have also been demonstrated in several studies. One study that used extracts from six brown seaweed species from Hong Kong found that they inhibited herpes simplex virus types 1 and 2, with very low toxicity to other cells.¹⁹ Another study found that polysaccharides from red and brown seaweeds prevented the viral replication of the hepatitis C virus.²⁰

More recently, in 2020, a study²¹ found that seaweed extracts exhibited promising results against SARS-CoV-2. Researchers from the Center for Biotechnology and Interdisciplinary Studies (CBIS) at Rensselaer Polytechnic Institute said that the extracts used a decoy technique, which has been found effective against other viruses like Zika, dengue and influenza A. In a news release published in Science Daily, they explained:²²

"The spike protein on the surface of SARS-CoV-2 latches onto the ACE-2 receptor, a molecule on the surface of human cells. Once secured, the virus inserts its own genetic material into the cell, hijacking the cellular machinery to produce replica viruses.

But the virus could just as easily be persuaded to lock onto a decoy molecule that offers a similar fit. The neutralized virus would be trapped and eventually degrade naturally."

What Else Can Seaweeds Do for You?

Seaweed’s superfood status is further supported by its many potential advantages for human health, as well as its sustainability. It’s regenerative — it does not require herbicides, pesticides, feed, irrigation and land to grow, making it one of the best zero-input crops today.²³

You can consume kelp and most varieties of seaweed raw, cooked and added into foods or served as a side dish or salad, or chopped in bits and added as a topping to your meals. Kelp supplements are also available today. Whatever form you choose, here are more potential benefits you can reap from this marine vegetable:

• May help lower your risk of cardiovascular events — A study found an inverse association between seaweed consumption and total stroke risk among Japanese men.²⁴ Another study noted that the polyphenol content of seaweed may be the reason for its cardioprotective benefits.²⁵

• Promotes thyroid health — Iodine deficiency is a growing concern today, which can pose a problem, as this nutrient is essential for proper thyroid hormone production.²⁶

  You cannot make iodine in your body; you need to get it from the foods you eat. Kelp is one of the top sources of iodine, and just a small amount can help you meet the recommended daily amounts.

  However, remember that you only need small doses of iodine. You need to balance your levels, as too much or too little can lead to either hypo or hyperthyroidism.

• May help manage diabetes — The alginic acid in seaweed is known for its positive effects on diabetes and blood coagulation. A 2011 study²⁷ found that kombu specifically has antihyperglycemic effects that may help reduce the risk of obesity and diabetes.

• May help promote brain health — Glutamic acid in dulse, which becomes glutamate in your body, is essential to your nervous system and may positively influence your memory, learning, cognition and normal brain function.²⁸

Astaxanthin — Another Marine Superfood

Macroalgae like seaweeds can offer impressive benefits, however, don’t miss out on the benefits of microalgae as well. In particular, the green microalgae Haematococcus pluvialis²⁹ contains the potent carotenoid astaxanthin, which can have tremendous advantages for your health.

Astaxanthin provides protection against reactive oxygen species and oxidation, which play a role in aging, cardiovascular disease, Alzheimer's disease and Parkinson's disease. Science Direct³⁰ refers to it as the "king of antioxidants," as it may be more potent compared to other antioxidants like vitamin A, vitamin E and lycopene. Although it’s related to beta-carotene, lutein and canthaxanthin, it has a unique molecular structure that sets it apart from other carotenoids.

Astaxanthin is available in supplement form. If you decide to give it a try, I recommend starting with 4 mg per day, and working your way up to about 8 mg per day — or more if you're an athlete or suffering from chronic inflammation. Taking this supplement with a small amount of healthy fat, such as butter or organic pastured eggs, will optimize its absorption.

The whole-body benefits of astaxanthin are so impressive, which is why this is one of the top antioxidants that I recommend you get more of. To learn more about the advantages of astaxanthin, you can read my article "Research on Astaxanthin Demonstrates Significant Whole Body Benefits."

Some Reminders Before You Load up on Kelp and Other Seaweeds

Going back to kelp and other seaweeds — while the benefits are promising, remember that you must be aware that they contain certain ingredients that, if consumed in excessive quantities, can have repercussions for your health.

For example, most seaweeds contain polyunsaturated fatty acids (PUFAs), including linoleic acid,³¹ which can be harmful to your health in excessive amounts. I believe it’s best to limit your LA consumption to 5 grams, or even better, 2 grams a day to protect your health.

Seaweed also contains some amounts of fluoride, which is a known neurotoxin that can lead to developmental problems in infants and young children, including mental difficulties and IQ reduction.³²

If you only consume small amounts of seaweed, however, the quantities will be too tiny to produce any drastic, long-lasting effect. To track your intake, I recommend using a tool like Cronometer, so you can keep an eye on how much LA you’re getting from your foods. Cronometer also provides information on other ingredients, like fluoride, in your foods. I recommend using the desktop site, though, as the mobile app does not show the complete list of nutrients.

Furthermore, I recommend being wise with your seaweed choices. You may be tempted to munch on products like dried laver seaweed sheets, for example, but these can be seasoned with artificial flavorings and vegetable oils like sesame oil,³³ which can add to your LA burden. As much as possible, opt for plain, unseasoned kelp and seaweed products.

Red seaweed varieties (Eucheuma, Chondrus, Hypnea and Gigartina) also contain carrageenan.³⁴ In its natural form, carrageenan has nutritional value and has even been noted to have anticancer potential.³⁵ However, this hydrocolloid, when used in food processing, undergoes an extensive treatment and extraction process that changes its chemistry, turning it into an ultraprocessed, synthetic ingredient.³⁶

As a result, carrageenan in food products has been linked to certain adverse effects, such as gastrointestinal disorders³⁷ and tumor formation in animal studies³⁸ due to its potential to trigger inflammatory pathways. The natural carrageenan in fresh seaweed likely wouldn’t cause any harm, but keep an eye out for the synthetic version — it’s mostly found in processed foods like pasteurized dairy, deli meats and canned soups.³⁹

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