Seaweed is a general term that refers to a number of algae and marine plants that grow along rocky shorelines around the world.
Some of the most common types of edible seaweeds include:
-
Wakame
-
Dulse
-
Kombu
-
Kelp
-
Sea lettuce
-
Nori
-
Arame
-
Chlorella
In prehistoric times, seaweed was an important part of coastal peoples’ diets.
Health Benefits
Seaweed is an excellent source of iodine, a vital trace mineral that plays a critical role in thyroid health. The body doesn’t make iodine on its own, so you need to get it from food sources or supplements.
Health benefits of seaweed include:
Improves thyroid function
Your thyroid plays a crucial role in your overall health, and iodine plays a vital role in its ability to function properly. Insufficient iodine means that your thyroid can’t make enough thyroid hormone (a condition known as hypothyroidism), which regulates many bodily functions, including metabolism. If you don’t get enough iodine, you may develop a goiter, a visible enlargement of your thyroid. Iodine deficiency can also impact children during development, both in the womb and during early childhood.
May improve gut health
Seaweed has carrageenans, agars, fucoidans, which act as prebiotics, non-digestible fibers that feed the healthy bacteria in your digestive tract. Sulfated polysaccharides (sugars found in seaweed) help to increase the growth of the good bacteria and increase the short-term fatty acids that keep the lining of your gut healthy.
Improves heart health
Some studies show that seaweed intake may help to reduce blood pressure. It may also help to reduce LDL cholesterol and total cholesterol levels. Results of human studies are promising, but more research is needed.
Stabilizes blood sugar levels
Brown seaweed contains fucoxanthin, an antioxidant that gives the vegetable its color. The antioxidant may play a role in helping to improve blood sugar control and reducing your risk of developing type 2 diabetes.
May boost your immune health. Some studies show that seaweed may help to boost your immune system by fighting viruses and preventing them from getting into your system. More studies are needed, however.
May reduce cancer risk. Adding seaweed to your diet may help to reduce your risk of developing certain types of cancer. It may decrease estrogen levels, which may reduce the risk of breast cancer. Again, there are very few human studies available, so more research is necessary.
Things to Watch Out For
Eating fresh seaweed is generally considered safe for most people. While the plant offers many health benefits, there are a few things to watch out for:
Too much iodine. While iodine is a vital trace mineral for thyroid health, too much can have the opposite effect.
May interfere with certain medications. Seaweed contains a high amount of potassium, which can be harmful to individuals with kidney disease. Seaweed also contains vitamin K, which could interfere with blood-thinning medications such as Warfarin.
Some varieties may have high levels of heavy metals. Some varieties of seaweed may contain high levels of arsenic, cadmium, mercury, or lead, depending upon how they’re grown. The FDA regulates the heavy metals in fresh seaweed, but not supplements.
How to Use Seaweed
Many grocery stores carry some forms of dried seaweed. You may find dried seaweed snacks, nori for sushi, or dried dulse flakes. Many Asian food stores carry a greater variety of dried and fresh seaweed products.
The British Dietetic Association advises against having seaweed more than once a week. Also, many seaweed products are pickled or fried and have added sugar and salt, so check the ingredients and nutrition labels first.