As you delve into the world of healthy eating, it becomes increasingly apparent that there are so many foods you ‘should’ be eating regularly in order to diversify your diet and fuel your body with essential nutrients. But at some point, it leaves you wondering if all of these ingredients could possibly be as healthy as they seem.

Case-in-point: seaweed. A staple of Asian cuisine for thousands of years, seaweed is touted as a must-have staple in a nutritious and varied diet. But is it really that good for you? We investigate its key benefits.


The short answer is yes: Seaweed really is a healthy, delicious food packed with a range of essential nutrients that will leave your body feeling great. “Seaweed is a nutrient-dense food and a good source of vitamins, minerals, fibre, fatty acids, protein, and other bioactive compounds like phytonutrients,” registered dietitian Molly Knudsen, M.S., RDN, explains. Other health benefits include:

1. Seaweed Can Have Antioxidant Properties

Foods that are rich in antioxidants can be of great benefit to the body (particularly for fighting free radical damage), and some seaweeds are thought to fit the bill.

“[Phytonutrients] often have antioxidant properties in the body and may offer health benefits when consumed, however more research is needed,” says Knudsen. “The nutritional composition of seaweed varies depending on the type (red, brown, and green) as well as the season and marine environment it’s grown in.”

Seaweed is also known to contain flavonoids and carotenoids, which fight off free radical damage within the body. In particular, brown seaweed contains a carotenoid called fucoxanthin that has a particularly impressive antioxidant effect.

2. Seaweed Provides Thyroid Support

Seaweed is also a major source of iodine, which supports a healthy thyroid. “Seaweed is an underrated ingredient. It’s the highest naturally occurring source of iodine that is well-absorbed,” explains registered dietitian Abby Cannon, J.D., R.D. “Iodine is essential for thyroid function; it’s an essential component of thyroxine (T4) and triiodothyronine (T3), two thyroid hormones.”

Caring for and supporting a healthy thyroid is important for hormone production and controlling your metabolism, and the iodine found in seaweed can help bolster thyroid function and hormone creation.

3. Seaweed Supports Healthy Digestion

Research has also revealed that seaweed may be useful in supporting smooth digestion and a happy gut. Cannon notes that seaweed contains fibre, which is vital for maintaining regular bowel movements and promoting general stomach comfort. Additionally, brown seaweed even contains sulfated polysaccharides, which may promote the growth of healthy gut bacteria.

4. Seaweed Contains Folate

Finally, seaweed is an abundant source of folate, a natural form of vitamin B9 that promotes the production of healthy new red blood cells and supports heart function.


Seaweed is undoubtedly great for the body, but there are a few things to be aware of when consuming this sea vegetable daily.

“There is the potential for seaweed to contain dangerously high levels of iodine and even arsenic species,” warns Knudsen (though this is more of a concern if you are taking supplements containing seaweeds versus eating it in its natural form). “If you are buying or consuming seaweed products regularly, see if the company, manufacturer, or a third-party reviewer discloses information on heavy metal testing,” she recommends. Cannon notes that otherwise healthy adults should not exceed 1,100 mcg of iodine each day.


With a salty umami flavour, seaweed makes its presence known in any meal or snack. As for how you can include more of this sea veggie into your diet, roasted seaweed is perhaps the most popular option, but seaweed salad is a great side to order with your sushi to pack in some greens for the day.

Seaweed also makes the perfect addition to soup and can even be dried and crumbled on top of salad to easily enhance the nutritional value and bold flavour. You might also like to try a greens powder.


There are so many wonderful, nutritious foods that you can fill your diet with to support daily function, but seaweed is one worth seriously considering eating more of. Offering gut health support, aiding in thyroid function, and providing a delicious umami flavour to complement your favourite soups, salads, and fish, sea vegetables should not be overlooked if your aim is to build a diverse and enriching diet.