©Photo by iStock: boommaval boommaval

Japanese Seaweed: The Superfood You Can Find Everywhere (And Should Be Eating)

All You Need To Know About The Types And Benefits Of Kaiso

By Emi Schemmer |
October 16, 2024 |
Food & Drink, Health & Beauty

Think twice before you remove that nori from your onigiri.

Since ancient times, Japan has used sea plants in various ways, including food sources, dietary supplements, plant fertilizers and medical treatments. Pastes made from Japanese seaweed were once used to heal burns, as it was believed they prevented bacterial infections and soothed the skin. In modern times, this practice is continued through the use of facemasks and seaweed-rich serums.

Kaiso (seaweeds) are also a staple of the Japanese diet. They’re an essential attribute of your miso soup, onigiri, sushi, salads and nori bento, among many more. Thanks to its numerous health and beauty benefits, widespread availability and cheap cost, Japanese seaweed has become a globally recognized staple food and beauty ingredient that we can easily incorporate into our lives. But before you rush to the supermarket, read on to learn more about the different types of kaiso, their benefits and ways to use them in your daily life. Here are six key players!

Nori
Kombu
Wakame
Hijiki
Mozuku
Aonori

See our Japanese seaweed beauty recommendations at the end of this list too!

1. Nori (海苔)

Nori is the most familiar seaweed. Although it looks green, it is actually a type of red algae. When dried out or roasted, takes on an almost black appearance. In its most common form, nori comes as roasted sheets.

With quite an impressive nutritional profile, nori is loaded with iodine, potassium and vitamin B12 and is low in calories, making it a healthy snack between meals. Iodine is a mineral that is essential for your metabolism and helps the thyroid gland to function properly. Consuming one sheet of roasted nori paper will give you about half of the daily recommended intake of iodine along with about 1.2 mg of vitamin B12—an essential vitamin that supports the normal functioning of the brain and nervous system as well as helps to form red blood cells.

How To Eat Nori

Wrap it around your makizushi, onigiri or mochi (after toasting and dipping it in soy sauce).
Add dried nori to your miso soup.
Try Gohan desu yo (ご飯ですよ！) paste by topping it on your rice or toast! It’s available at most supermarkets in Japan for around ¥280.

2. Kombu (昆布)

Kombu is an edible sea kelp that grows in long strips and looks exactly like what you think of if you picture seaweed washing up on the beach. Rich in calcium, Kombu has nutritional benefits that support cellular health and balance. It is a rich source of keratin and thus can contribute to shiny hair and strong nails.

Other notable health benefits include improving digestion and helping to reduce gas, improving thyroid function and helping with inflammatory diseases such as rheumatoid arthritis. It is also a great source of iron (which helps prevent anemia) and dietary fiber.

Kombu is also known for its umami properties. For this reason, it is one of the main ingredients in Japanese cuisine, used to make dashi (soup stock).

How To Eat Kombu

Use kombu stock for nabe, shabu shabu or other regular Japanese soups.
Stir-fry it with cabbage and other vegetables.
Drink kombucha, a common type of Japanese tea that is rich in minerals and aids in digestion. It is made from dried and powdered kombu.
Snack on dried kombu cuts like torobe (とろべ～). It’s available at most supermarkets in Japan for around ¥300.

3. Wakame (わかめ)

Wakame is another kind of sea kelp similar to kombu, but much more tender and succulent. It grows abundantly throughout the coastal regions of Japan and is extremely rich in vitamins A, C, D, E, K and B2, minerals such as iodine, calcium, iron, phosphorus, potassium, sodium, zinc and magnesium, and packed with antioxidants. Also, it contains a lot of folic acids, so it’s highly recommended for pregnant women or nursing mothers.

Wakame is a highly recommended ingredient for people with high cholesterol. It is rich in fucoxanthin, which stimulates the liver to increase the production of DHA, which is known for lowering the levels of LDL (i.e.: bad) cholesterol in your system. Since cholesterol is required as a building block for the production of estrogen, the cholesterol-lowering effects of wakame may also help to reduce the risk of certain estrogen-sensitive cancers.

Like other seaweeds, wakame can also balance weight (it is filling but extremely low in calories) and support thyroid health. Extremely rich in iodine—one of the essential components of our bodies’ hormonal balance and an integral aspect of creating the thyroid hormone—and omega-3 fatty acids, wakame helps boost our energy, reduce anxiety and fight depression.

How To Eat Wakame

Add it as an addition to pretty much everything, including:

Miso soup as well as other dashi-based soups
Salad
Udon
Spaghetti dishes that use Japanese sauces like tarako (cod roe) or soy sauce

4. Hijiki (ひじき)

Hijiki is a common seaweed found in most Japanese households and is usually sold in dried form (it sort of looks like dry black tea) in supermarkets. It is inexpensive, easy to prepare and loaded with nutritious health benefits.

Hijiki is rich in essential minerals such as magnesium, calcium, iron, as well as is a great source of healthy dietary fiber, which is why it is an essential ingredient recommended for people in need to improve their digestive health. Many Japanese still believe that regular consumption of this sea plant yields thick, black lustrous hair.

How To Eat Hijiki

Add it as an addition to salads or stir-fries.
Add hijiki to your rice before cooking it with a rice cooker.
Boil together with beans, carrots and other vegetables for a warm salad.

5. Mozuku (もずく)

Mozuku is a brown type of seaweed that is the pride of Okinawa. Nearly 100 percent of the world’s production is made in the southern archipelago of Japan, which is known for being the place with the longest human life expectancy. Though produced mainly in Okinawa, you can easily find it at any given supermarket across Japan, usually in small square packages in a vinegar dressing.

Mozuku is low in calories, high in minerals, and a special polysaccharide known as fucoidan, which makes it a wonderful anti-inflammatory, antioxidant and immune-boosting superfood.

It is also high in dietary fiber—so, once again, it’s good for your gut. It will help lower your blood sugar levels while keeping your gut microbes happy, healthy and in optimal functioning. Mozuku is also high in Vitamin K which is an essential vitamin associated with blood health. It regulates blood circulation and decreases the risk of clotting while lowering cholesterol levels.

How To Eat Mozuku

To make mozuku salad, mix mozuku (100g) with cucumbers (one whole) and other vegetables of preference.
Mix it in with natto (another slimy superfood), if you can handle it.

6. Aonori (青のり)

Aonori, although written and pronounced very similarly to nori, is actually a different species of sea algae than the regular nori. In Japan, it is most commonly used as a powder seasoning for a variety of dishes (including takoyaki and okonomiyaki), and it is often found in miso soup such as aonori jiru.

Good for your skin, digestion, healthy hair and even dental health, Aonori is filled with minerals, antioxidants and a wide range of vitamins. It is rich in vitamins like A, C, E, K and B complex vitamins like B1, B2, Niacin, B6, B12 and folate. Aonori also contains an impressive list of minerals such as calcium, sodium, potassium, magnesium, phosphorus, iron, manganese, zinc, copper, selenium, chromium and molybdenum.

Aonori is a great source of dietary fiber that helps improve digestion and control cholesterol levels in the body. It also provides a good amount of omega-3 fatty acids that help control the balance between good and bad cholesterol in our systems. The consumption of a small amount of aonori goes a long way in providing the daily requirement values of nutrients.

How To Eat Aonori

You can add it as a dry seasoning or extra flavor to any food including soups and omelets.
Add it as a topping for rice, toast and French fries

Japanese Seaweed Beauty Must-Tries

Lush’s Aqua Marina Facial Cleanser 100g (¥1,940): Aloe vera and seaweed combine for an ultra-gentle, softening cleanser. This unique product comes wrapped in a sheet of nori seaweed.

Shiro’s Konome Kombu Lotion 120mL (¥2,347): This moisturizing lotion created by soaking rare kombu that can only be found in the sea off the coast of Hakodate, Hokkaido is recommended for dry skin.

Algas’s All in one Cream 50g (¥2,913): A completely natural, mineral-rich moisturizing cream from Tokushima prefecture. It helps tighten, tone and firm the skin.

Mizuho’s Magic Soap of Moz 80g (¥2,420): This natural soap from Okinawa, made with mozuku extract, is perfect for dry and sensitive skin and helps with acne problems.

As you have already guessed correctly, seaweed is an inexpensive, easy to find and use superfood that will increase your well-being, detox your body and help boost your immune system. All types of seaweed have unique health-enhancing properties and can greatly contribute to your diet when eaten moderately. If you intake seaweed too excessively, this may increase the sodium levels in your blood and unbalance your diet in general. So, please don’t think of it as a substitute for your regular meals—but more of as a small, healthy addition to your daily diet.

Which Japanese seaweed is your favorite?

Japanese Seaweed: The Superfood You Can Find Everywhere (And Should Be Eating)