Low-calorie or sneaky snack? What to know about eating seaweed on a weight loss diet

Eating seaweed is becoming a popular choice as people look to improve their diets and nutrition.

Sometimes referred to as 'Vitamin Sea', these edible algae sea vegetables are a staple in Asian and Pacific cuisines and used to be found mostly in Asian grocery stores. The rise in popularity of both edible seaweed, dried seaweed and seaweed snacks means you can now find seaweed in almost every major supermarket and even some convenience stores.

But what do we really know about seaweed and its nutritional value?  Let's take a closer look at the health benefits of these marine plants.

What is seaweed?

Seaweed is a broad name that covers many species of plants and algae that grow in water. Seaweed grows on the rocky shorelines around the world and is a very versatile ingredient that can be used across many dishes.

These seaweed organisms are rich in both vitamins and minerals, including essential amino acids.

Seaweed species can be broken down into three main groups of species: red seaweed (scientific name Rhodophyta), green seaweed (or otherwise known as Chlorophyta), and brown seaweed (scientific names Ochrophyta and Phaeophyceae) [1].

Types of seaweed species

There are many types of edible seaweed you can incorporate into your diet. Here are the 10 most common:

Is seaweed good for you?

Seaweed has been classified as one of the so-called functional foods, sometimes called a nutraceutical because of its nutritional properties. Seaweed contains important antioxidants like polyphenols and carotenoids as well as omega-3 fatty acids. These phenolic compounds in seaweed are considered to be important for disease prevention [2]. Seaweed is even thought to have anti-cancer properties.

Seaweed is generally high in dietary fibre, minerals, vitamins and low in fat content. Seaweed is even being studied as an environmentally sustainable substitute for animal-based proteins [3].

Is seaweed high in calories?

Seaweed is actually a low-calorie food source. This is partly due to the high dietary fibre and water content of seaweed.

Is seaweed fattening? No. Both edible seaweed, fresh seaweed and dried seaweed are relatively low in calories. Consuming edible seaweeds in different forms is a helpful addition to a balanced diet.

There is also growing research into the benefits of seaweed on blood glucose levels. Seaweed extracts from the brown seaweed Ascophyllum nodosum show promising results in Canada for helping to maintain healthy blood glucose levels and reducing postprandial blood glucose [4].

Can seaweed help with weight loss?

Seaweed consumption can help with weight loss as part of a balanced diet. It's a relatively low-calorie snack or addition to any meal and can help as part of a holistic health protocol like Juniper's.

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What vitamins and minerals does seaweed contain?

There are many nutritional benefits to consuming edible seaweeds. This nutrient-rich plant food has iodine, iron, magnesium, vitamin A, vitamin B, vitamin C, Vitamin K and plenty of dietary fibre.

The dietary fibre in seaweed is great for gut health. Seaweed contains polysaccharides, which have been shown to increase the good bacteria in the human gut microbiota.

Is seaweed safe for everyone?

Eating seaweed has many possible health benefits as part of a balanced, healthy diet. Seaweed is also mostly consumed in small amounts, for example, a lunch of sushi rolls or a small packet of nori as a seaweed snack.

For most people, seaweed and seaweed snacks are perfectly fine to eat in moderation. For individuals with an existing thyroid function condition, people taking blood thinner medications, people with kidney failure and both pregnant and breastfeeding women should consult their doctor before incorporating seaweed frequently into their diets or taking seaweed extract dietary supplements.

How much seaweed can you eat safely?

Around 1 sheet of nori will give you almost 70% of your daily required iodine content.

Does this mean it's okay to eat seaweed every day? Well, it depends. Dried seaweed, like nori, can be an excellent source of nutrition, including vitamins and iodine. Frequently eating kombu or kelp that is extremely iodine-rich could result in a buildup of too much iodine.

The possible health benefits of seaweed really come down to adding these marine plants into your diet gradually. Eating seaweed is just another tool in your

Possible dangers of too much seaweed

Some preparations of seaweed can be high in sodium. Excessive sodium has been linked to heart health issues like high blood pressure or heart disease. Be sure to check the nutritional value, particularly on dried seaweed snacks.

There are also concerns about the toxic heavy metals like arsenic and mercury that can be found in seaweed, depending on where it is grown. If you are concerned about heavy metals, you can decrease the frequency with which you eat seaweed to every other day or a few times a week. You can also check the source of your seaweed and look for a reputable and trusted seaweed manufacturer.

Seaweed snacks are rich in iodine content. Iodine deficiency is becoming increasingly common as people are consuming less iodised salt in their diets. Even a minor iodine deficiency can impact your thyroid function.

Consuming edible seaweeds and seaweed snacks can be an excellent and simple way to consume enough iodine to reach the recommended daily amounts. Getting enough iodine through your diet is thought to be particularly important for young women, early pregnancy and in plant-based diets like vegetarian or vegan diets.

Too little or too much iodine can cause severe health problems like hyperthyroidism (overactive thyroid) and hypothyroidism (underactive thyroid) - both of which can have extremely serious health consequences. Seaweed can be part of a healthy diet and enjoyed in moderation. Varieties of dried kelp or kombu with the highest iodine content should be consumed moderately.

Ideas for incorporating seaweed into your diet

There are many ways to add seaweed to your diet. You can add seaweed seasoning to dishes like poke bowls or even use it as a salt replacement (hello iodine content!).

Whole seaweed can be used in seaweed salads with other sea vegetables sautéed in sesame oil or a rice vinegar dressing. You could also add whole seaweed to stir-frys, incorporate it into delicious soups, or even hide it in smoothies for a nutritional boost.

Dried nori seaweed can be eaten as delicious salty seaweed snacks by roasting or frying the dried seaweed until it's crispy. Other ways to eat dried nori include incorporating it into Japanese dishes like sushi rolls, California rolls, onigiri or even as a creative bread replacement for a wrap or sandwich.

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