Seaweed and Your Health: A Comprehensive Guide To The Benefits Of Seaweed

Seaweed and Your Health: A Comprehensive Guide To The Benefits Of Seaweed

Seaweeds are among the world’s oldest superfoods, long valued in many cultures for their nutritional benefits and health-enhancing qualities. Regular consumption of seaweed has been shown to reduce the impact of menopause symptoms, and improve thyroid, heart, and gut health. Seaweed is also associated with health and longevity in the world famous “Blue Zone” Okinawan and Mediterranean diet.

If you’re new to the delicious taste and nutritional goodness of seaweed, think of them as “vegetables from the sea”. Like leafy greens on land, seaweeds are jam-packed with beneficial nutrients. They're a natural source of antioxidant vitamins A, C, E, brimming with B-vitamins, and boast essential minerals like calcium, iodine, and iron. Ready for more? Seaweed also packs protein, fiber, and mood-supporting Omega-3 fatty acids. In fact bite for bite, many types of seaweed have better quality and more nutrient density than found in kale and spinach.

What does seaweed taste like?

Like other leafy greens, seaweed has a range of taste and flavor depending on the type of seaweed and how it is prepared. From a bright zingy seaweed nestled alongside fresh fish in a poke bowl, to the traditional “umami” flavor of a nori sushi roll, to a slice of kombu simmered in beans to add rich flavor. And in our Daily Bites, seaweed is blended with dates, almonds, seeds and other flavors to produce a slightly sweet, nutty, and very tasty treat. 

What is seaweed and why is it good for me?

Seaweed comes in a vast array of shapes, sizes, and colors. Seaweed thrives in a variety of underwater environments, from coastal shallows to deep-sea floors. There are over 12,000 species of seaweed.

From the rich Nori wrapped around sushi rolls, to ruffle-edge “sea lettuce”, to kelp that forms forest-like underwater landscapes, seaweed is as diverse as it is nutrient-dense. Kelp, a large brown seaweed, forms underwater forests and is a powerhouse of iodine and other nutrients. Laver, often referred to as the "Welshman's caviar," is rich in proteins and vitamins, contributing to its popularity in various cuisines.

Seaweed and human evolution

“Seaweed” is a general term for a diverse group of marine algae that holds a special place in the history of human evolution. Our ancestors discovered its nourishing properties thousands of years ago, using it as a reliable source of food and medicine. Some research even suggests that the nutrients in seaweed (including iodine, zinc, and omega-fatty acids) may have helped power human brain development two million years ago.

Seaweed remains a cornerstone of many global food and medicine traditions. It's much more than a marine vegetable; it's a testament to human adaptability and resourcefulness. For millennia, various cultures, including those in China, Japan, Korea, and Polynesia have prized seaweed for its nutritional value and health-enhancing qualities. Till today, seaweed is used in a broth for postpartum recovery!  

The nutritional composition of seaweed

Each species of seaweed is packed with different kinds of nutrients. Broadly, they're a natural source of vitamins like A, C, E, and several B-vitamins, minerals like calcium, iodine, and iron, as well as proteins, fiber, and omega-3 fatty acids. Some types of seaweed outcompete the nutrient density of kale and spinach!

One key nutrient most species of seaweed harbor is iodine, essential for thyroid function; seaweed is the most potent natural source of iodine.

Seaweed in the Blue Zones

Blue zones, regions where people live significantly longer than average, have diets rich in whole, nutrient-dense foods, including seaweed. People in these regions often live into their 100s and enjoy a vitality that lasts throughout their long lives.

Japanese populations in particular, renowned for their longevity, include seaweed as a staple part of their diet. Their diets also include whole, nutrient-dense foods, like legumes, whole grains, fruits, and vegetables. The Okinawa region in Japan, known for its high number of centenarians, includes seaweed as a dietary staple, contributing to its citizens' longevity and lower rates of age-associated diseases like diabetes, cancer, and cardiovascular disease.

Major Health Benefits of Seaweed

Thyroid health 

Seaweed is making waves in health and wellness in particular because it is one of the most potent natural sources of iodine in the world. Iodine is an essential mineral we need in our diets for optimal thyroid function. The thyroid gland—a butterfly shaped endocrine gland located on the lower part of your neck—needs iodine to produce hormones that regulate energy and metabolism, as well as power healthy functioning of your brain, heart, muscles and other organs. Without enough iodine, an underactive thyroid (a condition where the thyroid doesn’t produce enough hormones) can result, causing fatigue, weight gain, and depression. 1 in 10 women have been diagnosed with thyroid problems.

The Recommended Dietary Allowance (RDA) for iodine in adults is 150 μg per day. 1 serving of Rootless Daily Bites provides your complete dose of daily iodine as well as a host of other essential minerals, vitamins, fiber and heart healthy fats. 

Heart Health

Researchers have found that regular seaweed consumption can help lower cholesterol levels, reducing the risk of heart disease. The credit goes to its high fiber content and unique polyphenols that possess blood-pressure-lowering effects, specifically porphyran.

Porphyran, found in seaweeds like Nori, has been studied for its potential to lower blood pressure and cholesterol levels, thereby reducing the risk of heart disease.

Menopause symptom alleviation

A recent study evaluated seaweed's impact on the health of postmenopausal women with hot flashes. Results showed that women with lower iodine levels had more hot flashes. In addition, researchers found increased levels of lipoprotein(A) or Lp(a) in the blood. Lp(a) is a strong risk factor marker for cardiovascular concerns, far more of an indicator than cholesterol levels. Low iodine status was found with two prevalent concerns linked with menopause – hot flashes and increased Lp(a).

Gut health

The fiber in seaweed acts as a prebiotic, naturally feeding the beneficial bacteria in your gut. This benefits not only a healthy digestive system, but also boosts your immune system. A robust gut microbiome is increasingly being recognized as a cornerstone of overall health.

Weight management

Seaweed is a low-calorie food packed with nutrients, which makes it ideal for weight control. Its high fiber content aids in satiety, helping to reduce overeating.

Skin health

Not only is seaweed beneficial as a superfood for the body, but it also has advantages for the skin. With a treasure trove of antioxidants, seaweed fights against skin-damaging free radicals that can improve skin health and slow the aging process. Its hydrating properties can help combat dry skin, while its rich mineral content aids in maintaining skin temperature regulation and retaining moisture.

Iodine Intake During Pre-Conception, Pregnancy, and Postpartum

Iodine is crucial during pre-conception, pregnancy, and postpartum stages. It plays a critical role in maternal health and fetal cognitive development during pregnancy. 

Recent studies, such as this one from the National Institute of Health, have noted the re-emergence of iodine deficiency in these specific populations, putting a significant percentage of the world population at risk. Iodine deficiency can also impact egg freezing and fertility outcomes. Severe iodine deficiency during pregnancy has been shown to cause stunted physical and cognitive fetal development.

Women of reproductive age, especially those planning to conceive, have increased iodine requirements. For reference, the recommended daily amount of iodine for an adult is 150 mcg, compared to 220 mcg per day for pregnant people, and 290mcg for lactating people. 

Importance of Iodine Consumption for Vegetarians and Vegans

Vegetarians and vegans, who may lack iodine from the absence of seafood and dairy in their diets, can significantly benefit from incorporating seaweed. This plant source of iodine can help fill nutritional gaps and support overall health. Apart from seaweed, other plant-based iodine sources include iodized salt, prunes, and iodine-fortified foods. However, seaweed stands out as a potent, natural source of iodine among these.

With the popular trend of using 100% natural or specialty salts in recent years (such as Himalayan, sea salt, etc), there’s been a gradual shift away from iodized salt in the U.S. Thoughtfully adding iodine-rich foods may be a good idea if you aren’t eating foods like fish, seaweed, shrimp, or dairy, are following a low sodium diet, or have switched to an all natural (and therefore non-iodized) salt.

Our Sourcing Standards: Organic, Sustainably Grown, Tested for Purity

We carefully source our seaweed for all our Rootless products from two of the pioneers in organic, verified, sustainably sourced seaweeds.

  • Maine Coast Sea Vegetables grows seaweeds in the clear, cold waters off the coast of Maine. They are a category leader in sustainability practices. They conduct extensive 3rd party testing for purity, so you can have confidence in every delicious bite.
  • Wild Irish Seaweeds have been harvesting wild organic seaweed from the west of Ireland for over 100 years. They only harvest in season to ensure the nutrient profile of their seaweed is at its peak.

How to Incorporate Seaweed into Your Diet

Adding seaweed to your diet is simpler than you might think. From traditional dishes to modern innovation, look for fresh, dried, prepared seaweed in your favorite grocery store, and try these easy daily ways:

  • Rootless Daily Bites
  • A handful of seaweed salad in your lunch power bowl
  • Miso soup
  • Sushi rolls
  • Dulse or Furikake sprinkled on avocado toast or popcorn

We hope you are as excited about the possibility of seaweed to improve and support your well-being as we are. Email us at with any questions. We love to talk seaweed!

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