Seaweed is a nutrient-packed food gaining popularity for its health benefits, including improving metabolism, supporting heart health, and aiding blood sugar control.

Here's why you should consider adding it to your diet:

• Rich in nutrients: High in fibre (35–60% by dry weight), iodine, vitamin B12, and antioxidants.
• Supports metabolism: Iodine aids thyroid function, which regulates metabolism, while fibre stabilises blood sugar.
• Heart health: Compounds like fucans and polyphenols help lower cholesterol and blood pressure.
• Weight management: Promotes fullness, reduces fat absorption, and supports fat metabolism.
• Sustainable: Grows rapidly and helps the environment by capturing carbon.

Quick tip: Add seaweed to soups, salads or snacks but keep an eye on your iodine intake to stay within safe limits. Kombu is particularly high in iodine while nori and wakame offer gentler options.

Seaweed is not just a nutrient-dense and sustainable food choice. It can also support better blood sugar balance. With Vively’s continuous glucose monitoring, you can see how different types of seaweed affect your levels and make informed food choices. Keep reading to explore the benefits, nutrition and safe ways to add seaweed to your diet.

Seaweed nutrition facts

A mere 7-gram serving of dried seaweed packs a punch with essential vitamins, minerals, and antioxidants, making it a nutrient-rich addition to any diet – even in small amounts.

Main nutrients

Dried seaweed is loaded with essential nutrients. For example, its fibre content alone makes up 35–60% of its dry weight, providing over 12.5% of the daily fibre requirement in just an 8-gram serving.

Here’s a closer look at its key nutritional components:

Types of seaweed

Each type of seaweed brings its own unique nutritional profile to the table:

• Nori: A 5-gram serving of dried nori contains roughly 7 calories, 1.5 grams of protein, 3 grams of fibre, 73.5 mcg of iodine, and 1.4 mcg of vitamin B12.
• Kombu: Known for its incredibly high iodine content, kombu delivers a staggering 9,333% of the Daily Value for iodine in a 7-gram serving, along with 13% of the Daily Value for magnesium and 14% for potassium
• Wakame: This nutrient-dense seaweed provides about 5 calories per 2-tablespoon serving while offering 75% of the Daily Value for iodine and 24% for magnesium.

Effects on metabolism

Seaweed’s nutrient-rich composition plays a vital role in supporting metabolic health. Its iodine content is particularly important for thyroid function, which regulates metabolism. Since the human body cannot produce iodine, dietary sources like seaweed are crucial.

Additionally, the fibre in seaweed contributes to metabolic benefits by:

• Slowing digestion for a steadier energy release,
• Acting as a prebiotic to nourish beneficial gut bacteria,
• Helping stabilise blood sugar and insulin levels.

Emerging research backs these benefits. For instance, a 2023 meta-analysis found that consuming brown seaweed may significantly improve blood glucose control and markers of insulin sensitivity. Up next, we’ll explore how seaweed helps with blood sugar regulation.

Blood sugar control with seaweed

Seaweed isn’t just packed with nutrients. It also plays a unique role in managing blood glucose. Its natural compounds, including fucoxanthin and fibre, help slow digestion, improve insulin response and reduce post-meal glucose spikes.

How fucoxanthin works

Fucoxanthin, a carotenoid found in brown seaweed, plays a role in regulating blood sugar. With an antioxidant capacity 13.5 times greater than vitamin E, it works through several mechanisms:

• Regulating adipokine production
• Enhancing hepatic glucokinase activity
• Modulating glucose transporter expression
• Supporting pancreatic beta cell function

A 2021 study highlighted that fucoxanthin extracted from Sargassum angustifolium significantly reduced fasting blood glucose levels and boosted insulin production, showing effects comparable to metformin. These mechanisms explain the promising blood sugar benefits observed in recent research.

Research on blood sugar effects

A 2023 meta-analysis provided insights into the effects of different seaweed types on blood sugar:

Additionally, a 2023 study involving Korean adults with normal weight found that individuals with the highest seaweed intake had a 7% lower risk of developing type 2 diabetes compared to those who consumed the least.

Using seaweed in meals

Incorporating seaweed into your diet can help manage blood sugar levels. Here’s how you can make it part of your meals:

1. Pair with carbohydrates
Add seaweed to carb-heavy meals to slow sugar absorption. The fibre in seaweed helps reduce the speed at which carbohydrates are digested and absorbed.

2. Optimal timing
Aim for at least 1,000 mg of seaweed daily to support blood sugar control. Try these meal ideas:

• Blend wakame into your morning smoothie.
• Use nori sheets for lunch wraps.
• Add kombu to soups for dinner.

3. Synergistic Combinations
Combine seaweed with other nutrient-dense foods for enhanced effects. For example, pair wakame with beans, mix arame with whole grains, or cook kombu with legumes.

Certain polyphenols in Ascophyllum nodosum can inhibit alpha-amylase, an enzyme that breaks down carbohydrates, leading to a more gradual release of sugar into the bloodstream.

Looking for breakfast ideas that support balanced blood sugar? Check out our list of the healthiest low GI breakfast options in Australia for practical inspiration.

Other health effects

Seaweed isn't just about managing blood sugar – it brings a host of other benefits that can support overall health.

Digestive health impact

Packed with fibre, seaweed is a fantastic ally for digestive health. Even a small serving of dried nori can help meet daily fibre needs, benefiting gut function.

Seaweed contains bioactive carbohydrates like fucoidan, laminarin, and alginate, which act as prebiotics. These compounds encourage the growth of beneficial gut bacteria and increase the production of short-chain fatty acids (SCFAs), which nourish the cells lining your digestive tract. This ripple effect can even contribute to better heart health.

Heart health benefits

Seaweed's benefits go beyond digestion - it also supports heart health. A 2023 meta-analysis found that regular consumption of brown seaweed significantly lowered total cholesterol and LDL (the "bad" cholesterol) levels.

Interestingly, Japan, where seaweed is a dietary staple, has some of the lowest rates of cardiovascular disease globally.

Here's how seaweed promotes heart health:

Weight management properties

Seaweed can also play a role in weight management by promoting fullness, enhancing fat metabolism, and reducing fat absorption. A 2023 clinical trial with 28 participants suffering from metabolic syndrome found that fucoxanthin supplementation led to noticeable reductions in body weight, blood pressure, and triglycerides.

Daily seaweed intake before meals has been shown to reduce energy consumption by about 7% (134.8 fewer calories per day) This happens because:

• Its high fibre content slows digestion, helping you feel full longer.
• Fucoxanthin stimulates fat breakdown and fatty acid oxidation.
• Alginates inhibit fat absorption in the gut.

In a 14-week randomised, double-blind trial, participants who consumed 15 grams of alginate daily lost an average of 2.67 kg, significantly more than the control group, which lost just 0.91 kg. These results highlight seaweed's potential as a natural tool for managing weight.

With such a wide range of benefits, seaweed is a smart addition to any balanced diet.

‍Want to eat well without overspending? Explore our practical tips for staying healthy on a budget while still supporting your metabolic goals.

Adding seaweed to your diet

Adding seaweed to your meals can be both simple and effective. Whether you're tossing nori into a salad or using kombu in soups, even small amounts can deliver noticeable benefits for metabolic health, energy, and digestion.

Safety guidelines

When incorporating seaweed into your meals, it's important to keep iodine intake in check. For adults, the recommended daily allowance (RDA) for iodine is 150 micrograms, with an upper safety limit of 1,100 micrograms. Since iodine levels in seaweed can vary widely, tracking your overall consumption is key:

To reduce the risk of heavy metal exposure:

• Choose organic seaweed from trusted sources.
• Avoid hijiki, as it contains high levels of inorganic arsenic.
• Rotate between different seaweed types.
• Practice moderation when consuming seaweed.

Cooking methods

The way you prepare seaweed can enhance its nutritional value and help manage iodine levels. Here are some tips for getting the most out of your seaweed:

Rehydrating dried seaweed

• Thin varieties like nori: Soak in cool water for 5–10 minutes.
• Thicker types like kombu: Soak for 20–30 minutes to fully hydrate 

Cooking techniques

• Steam wakame or sea lettuce for 3–5 minutes to retain nutrients
• Boil kombu for 15 minutes to reduce iodine content by up to 99%
• Roast nori at 300°F for 5–10 minutes for a crispy, snackable texture.

Try these techniques with simple recipes to add seaweed to your diet effortlessly.

Quick seaweed recipes

Classic wakame salad
Combine rehydrated wakame with:

• Rice vinegar
• Toasted sesame oil
• Minced garlic
• Sliced scallions
• Sesame seeds

Umami-rich bean broth
Drop a 2-inch strip of kombu into your pot when cooking beans. This method enhances flavor while infusing the dish with minerals. Remove the kombu before serving.

Nori seasoning blend
Make a versatile topping by grinding together:

• Dried nori sheets
• Dried kombu
• Dulse flakes
• Sesame seeds
• Black pepper
• Sea salt

Sprinkle this blend on rice, vegetables, or soups for a quick boost of flavour and nutrients.

How Vively helps you personalise your seaweed intake

The benefits of seaweed are well-documented, but its glucose impact can still vary depending on what it’s paired with. That’s where Vively’s continuous glucose monitoring (CGM) program becomes an essential tool. Instead of relying solely on general nutrition advice, you get real-time feedback on how specific foods affect your body.

For example, as the chart above shows, eating pure seaweed resulted in a modest glucose rise to 5.2 mmol/L, while a typical onigiri spiked glucose to 7.3 mmol/L. That difference may not seem huge at first glance, but over time, repeated spikes may contribute to insulin resistance and metabolic dysfunction. Understanding how your glucose responds to seemingly similar foods is key to making better decisions long-term.

With Vively, you can:

• Track how seaweed and its meal pairings affect your personal glucose response
• Learn which food combinations support stable blood sugar
• Receive tailored food scores and pairing suggestions inside the app
• Access expert support from qualified dietitians to help you adapt traditional recipes
• Monitor your Metabolic Health Score to see how daily meals influence your long-term patterns

By combining your CGM data with expert coaching, you can build a seaweed-inclusive diet that’s both nutritionally beneficial and metabolically supportive.

Ready to see how your favourite meals affect your blood sugar? Start your Vively journey today.

Conclusion

Seaweed offers a range of benefits for metabolic health, including lowering post-meal blood glucose, HbA1c levels, and markers of insulin resistance.

Packed with fibre, making up 35–60% of its dry weight – it supports digestive health and helps regulate blood sugar. Even a small amount, like 2 mg of fucoxanthin, has been shown to positively impact blood sugar levels.

What makes seaweed stand out is its rapid growth – up to thirty times faster than land vegetables – which adds an eco-friendly edge to its nutritional profile. Just 8 grams of seaweed can supply over 10% of your daily fibre needs, blending sustainability with significant dietary benefits.

With global diabetes cases projected to reach 643 million by 2030, adding seaweed to a balanced diet could be a practical step in managing blood sugar levels.

Beyond its role in metabolic and heart health, seaweed delivers a rich mix of minerals and compounds like alginate, which help stabilise blood sugar when included in a balanced diet and consumed mindfully.

With Vively, you can track how seaweed influences your glucose levels in real time, giving you clearer insight into how your food choices impact your metabolic health.

FAQs

How can I add seaweed to my diet without consuming too much iodine?

To enjoy seaweed safely while keeping your iodine intake in check, it's essential to pay attention to both the type and amount you eat. Adults generally need 150 micrograms of iodine daily, while pregnant and breastfeeding women require slightly more – around 220–290 micrograms. Seaweed varieties like nori, kelp, and wakame differ significantly in their iodine content. For instance, just 10 grams of dried nori can deliver over 200 micrograms of iodine.

To prevent overdoing it, stick to small servings, such as 3–7 grams of dried seaweed or 9–21 grams of fresh seaweed, and limit consumption to 1–2 times per week. This way, you can enjoy seaweed's perks - like fibre, antioxidants, and essential minerals – without surpassing safe iodine levels.

What types of seaweed are best for supporting heart health and managing blood sugar levels?

Some excellent seaweed options for promoting heart health and managing blood sugar include brown seaweed varieties like kombu and wakame, as well as nori. Brown seaweed is packed with dietary fibre and antioxidants, which may help improve cholesterol levels and lower the risk of type 2 diabetes. Meanwhile, nori is a good source of omega-3 fatty acids, which play a role in supporting overall metabolic health.

You can easily work these seaweed types into your meals. Try wrapping sushi with nori or tossing wakame into soups and salads for a tasty way to support your heart and metabolism.

Can eating seaweed regularly cause any health risks or side effects?

While seaweed packs a nutritional punch, eating it too often or in large amounts can come with some risks. One of the main concerns is excessive iodine intake, which can potentially lead to thyroid problems like hyperthyroidism or goitre. On top of that, certain types of seaweed can absorb trace amounts of arsenic, and consuming too much over time might pose health risks.

You might also experience digestive issues or even a mild laxative effect if you overdo it. Plus, seaweed could interfere with thyroid medications, so if you have thyroid-related health conditions or are on medication, it’s a good idea to check with your doctor first. For most people, enjoying seaweed in moderation as part of a varied diet is a safe and healthy choice.