The Health Benefits of Seaweed

Mara Seaweed flakes piles

Why is seaweed so healthy?

Seaweed is so good for us because it’s packed with nutrients. Seaweed absorbs minerals directly from sunlight and the ocean. When seaweed is dried, moisture is removed and the minerals become more concentrated.

Seaweed is the most mineralised vegetable on Earth. It contains all 56 elements essential for our health in a similar ratio to human blood. It’s a good source of fibre, protein, calcium, iron and iodine. Seaweed is low in fat, suitable for vegans and gluten-free. That’s why we call it 'the superfood of the sea.’

Seaweed for a modern diet

The only nutritional element missing in edible seaweed is calories. But as Western cultures continue to struggle with overeating, this may not be a bad thing. Instead, seaweed is high in fibre, which can make you feel fuller for longer and reduce snacking.

Seaweed is also able to provide nutrients which are often missing from crops grown in mineral-depleted soils. This means it has a unique ability to fill gaps in the modern diet.

If you’re after more detailed information, we highly recommend this research paper. You can also find further resources at the end of the blog.

Seaweed compared to other food

Seaweed is essential for everyday health, and in some cases nutritionally superior to other food, gram for gram.

The table below outlines some of the nutrients contained in seaweed and what they do for your body. This combination of vitamins, minerals, electrolytes and trace elements isn’t found in any other land or sea vegetable.

Seaweed is unique in its ability to deliver all of these health benefits in one go, and all it takes is just 1 teaspoon of Mara Seaweed a day.

Naturally, there are variations in the concentrations of nutrients in seaweeds due to variety and seasonality.

Nutrient (high in seaweed)

What does the nutrient do?

How does seaweed compare to other foods?


Iodine regulates the thyroid gland. The thyroid helps to maintain thinking and reasoning, your metabolism, body temperature and heart function.

No other food is such a good source of iodine, particularly other so-called ‘superfoods’ such as spirulina.


The combination of soluble and insoluble fibre in seaweed promote good gut health and create a bulking agent that helps food move more easily through the body.  

2g of seaweed is higher in fibre than the equivalent quantity of spirulina, sunflower seeds, coconut meat or pine nuts. Fibre also helps you feel fuller, helping with weight management.


Seaweed is one of the best vegetable sources of calcium, which is essential for building strong bones and teeth.

2g of seaweed contains more calcium than 2g of spirulina, sunflower seeds, or flaxseeds.


Seaweed is a good source of protein for vegetarians and vegans. It contributes to the maintenance of normal bones and muscle mass.

Seaweed contains a similar amount of protein to pine nuts.


Iron is part of all body cells and helps muscles to store and use oxygen. This helps fight tiredness and fatigue.

One 2g serving of Dulse seaweed contains almost twice as much iron as sunflower, chia or flax seeds.


Potassium prevents high blood pressure and improves cardiovascular health.

One serving provides 4-8% of daily recommended potassium intake, more than spirulina, pine nuts or flaxseeds.


Magnesium helps to maintain normal function of the nervous system.

2g of Kombu kelp or Shony contains more magnesium than chia seeds, flax seeds or sunflower seeds.

Vitamin C

Vitamin C accelerates healing and prevents colds, but it also with the absorption of iron.


B Vitamins

B vitamins are critical to maintaining normal metabolism, enhancing the immune system and combating stress.




Seaweed contains just the right amount of sodium for the correct balance of body fluids, 85% less than in salt.

Even iodized salt, which contains iodine to help address deficiencies, cannot offer the other added health benefits naturally found in seaweed.

For more detailed information, a table of nutritional contents can be found under each product in our shop.

Can I eat too much seaweed?

As with anything, moderation is key. However, there are few dramatic side effects to consuming too much seaweed. Symptoms may include dizziness and feeling tired, rather than energised. 

In most cases, this is the result of hyperthyroidism, or an overactive thyroid due to too much iodine, which is rare. Iodine is water soluble which means it’s easily absorbed by the body - but also easily removed. The body uses what it needs and the rest is excreted in through urine.

If you normally enjoy seaweed and it starts to seem unappealing, listen to your body and stop eating it. The side effects will soon fade away.

Further resources

Discover nutritional facts about seaweed, try our other health blogs, or take some time to look through the following research papers.


Visit the Seaweed Shop 


  • It was quite interesting to learn that seaweed is packed with nutrients since it absorbs minerals directly from sunlight and the ocean. I wanted to make seaweed soup since the weather has been quite cold lately, so I need the ingredients for it soon. I’ll keep this in mind when I go shopping for fresh seaweed later.

    Elina Brooks
  • Woah, I had no idea that as it includes all 56 of the elements necessary for our health in a proportion close to that of human blood, seaweed is the most mineralized vegetable on Earth. As a vegetarian, I am always looking for ways to incorporate new vegetable I can add to my diet that is filling, nutritious, and safe to eat. I believe that fresh seaweed is all of those qualities after reading your article so I’ll look into a trustworthy supplier. Thanks.

    Taylor Abrams

Leave a comment

Please note, comments must be approved before they are published