Which Seaweed Is High in Fatty Acids?

December 21, 2025 •

5 min read

Several studies confirm that some brown and green seaweeds contain a higher total fatty acid content compared to red seaweeds. These marine superfoods offer a sustainable, plant-based way to obtain beneficial healthy fats, providing key insights into which seaweed is high in fatty acids for your dietary needs.

Quick Summary

Many brown, red, and green seaweed species are excellent sources of omega-3 fatty acids like EPA and DHA. Key types include nori, wakame, and certain kelps, which provide healthy fats crucial for human nutrition and overall wellness.

Key Points

Brown Seaweeds: Species like Sargassum muticum and Undaria pinnatifida (wakame) are notable for their high content of polyunsaturated fatty acids (PUFA) and highly unsaturated fatty acids (HUFA), including beneficial EPA and DHA.
Red Seaweeds: Dulse (Palmaria palmata) and Calliblepharis jubata are particularly rich in EPA and HUFA, respectively, making them excellent sources of omega-3s.
Green Seaweeds: While green seaweeds can have good total fatty acid content, some specific species like Ulva compressa may have a profile dominated by saturated fats, while nori offers a good source of PUFAs.
Nori: Often used for sushi, nori is a mild-tasting seaweed containing healthy omega-3 fatty acids, specifically a high percentage of EPA.
Wakame: Contains fucoxanthin, a compound that can stimulate the body's production of DHA, alongside its inherent omega-3 content.
Supplementation: Since the fatty acid content in whole seaweeds can be relatively low, especially for DHA, algae-derived supplements are an effective option for vegans and vegetarians seeking a direct source.
Environmental Factors: The fatty acid profile of any given seaweed can vary depending on its harvest location and the season due to environmental factors like temperature and nutrients.

Understanding Fatty Acids in Seaweed

Seaweeds, or marine macroalgae, are a diverse group of organisms that are an essential part of marine ecosystems. While often thought of primarily for their high mineral and vitamin content, they are also a valuable source of fatty acids, particularly beneficial polyunsaturated fatty acids (PUFAs) like omega-3s. Unlike terrestrial plants, which primarily contain the precursor alpha-linolenic acid (ALA), many seaweeds can produce longer-chain omega-3s, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). The specific fatty acid profile varies significantly between species and is also influenced by environmental factors such as temperature, light, and nutrient availability.

Brown Seaweeds: A Potent Source of PUFAs

Brown seaweeds (Phaeophyceae) are often cited for their relatively high fatty acid content, particularly EPA. These include species such as:

Sargassum muticum: Research has identified this species as having a notably high total fatty acid content, with a significant contribution from highly unsaturated fatty acids (HUFA). It is also known to contain DHA.
Undaria pinnatifida (Wakame): A popular edible seaweed, wakame is a good source of omega-3 fatty acids. It also contains fucoxanthin, a compound that has been shown to stimulate the production of DHA in the body.
Kelp Varieties: Certain kelp species, like Laminaria hyperborea, also contain valuable omega-3s and other healthy fats.

Red Seaweeds: Another Contributor to Healthy Fats

Red seaweeds (Rhodophyta) also contribute to the fatty acid intake, with certain species standing out for their high levels of specific omega-3s.

Palmaria palmata (Dulse): This red algae is particularly interesting as it can contain high proportions of the omega-3 fatty acid EPA.
Calliblepharis jubata: This species has shown high levels of HUFA and an excellent omega-6 to omega-3 ratio, suggesting significant nutraceutical potential.

Green Seaweeds: Variable but Present

While brown and red seaweeds are often richer in PUFAs, green seaweeds (Chlorophyta) also contain fatty acids, though the profile can be more saturated in some cases.

Ulva spp. (Sea Lettuce): Some Ulva species have a high total fatty acid content, though their composition can vary widely depending on the growing season.
Nori (Pyropia tenera): This popular seaweed, used for sushi rolls, is a source of omega-3s, with a high proportion of its fatty acids coming from polyunsaturated types like EPA.

Comparison of Seaweed Fatty Acid Profiles

The fatty acid composition of seaweed can vary widely. The following table provides a general overview based on available research, highlighting key fatty acid types often found in brown, red, and green seaweeds. The content can change based on species, harvest location, and season.


Seaweed Type	Key Omega-3s	Notable Fatty Acids	General Fatty Acid Profile	Notes
Brown	EPA, DHA (in some)	ARA, Myristic Acid	Often good source of PUFA	High EPA levels are common
Red	EPA, DHA	Palmitic Acid	High HUFA content possible	Profile can be quite variable
Green	ALA, EPA	Palmitic Acid (often highest)	Higher SFA content possible	Can have good total FA but less ideal ratio
*Nori (Pyropia)*	EPA	Palmitic Acid, Oleic Acid	Significant PUFA content, especially EPA	High protein and fiber alongside fats
*Wakame (Undaria)*	DHA (stimulated)	Fucoxanthin (not a FA)	Good source of omega-3s, supports DHA synthesis	Low calorie, good for weight management
*Dulse (Palmaria)*	EPA	Palmitic Acid	Good EPA content, softer texture	Can also be high in protein

The Role of Environmental Factors

The fatty acid profile of seaweed is not static. Environmental conditions play a significant role in determining the quantity and composition of lipids. Studies show that factors such as water temperature, salinity, light exposure, and nutrient availability all influence the biochemical makeup of these organisms. For example, some species may produce higher levels of PUFAs when exposed to colder waters, while seasonal changes can also cause fluctuations in fatty acid content.

Practical Ways to Incorporate High-Fatty Acid Seaweed

Integrating seaweed with a beneficial fatty acid profile into your diet is straightforward and can add unique flavors and textures to meals. Here are some ideas:

Snack on Nori: Nori sheets, commonly used for sushi, can be enjoyed on their own as a salty, nutrient-rich snack. It provides a source of omega-3s, particularly EPA.
Add Wakame to Soups and Salads: Wakame expands when rehydrated and adds a soft texture to miso soup or refreshing salads. It provides omega-3s and supports DHA production.
Use Dulse as a Seasoning: Dulse flakes can be sprinkled over salads, baked potatoes, or popcorn for a chewy texture and a boost of EPA.
Flavor Broths with Kombu: Kombu, a type of kelp, is a traditional ingredient in dashi broths and stews. It adds an umami flavor and can contribute to your fatty acid intake.
Mix into Smoothies: Powdered forms of seaweeds or microalgae like spirulina and chlorella can be mixed into smoothies for a concentrated nutrient boost, including omega-3s.

Algae Supplements: A Concentrated Alternative

While whole seaweed is a healthy food, the amount of DHA and EPA can be relatively small compared to what is needed for therapeutic benefits. For individuals, particularly vegans and vegetarians, looking for a concentrated and reliable source of EPA and DHA, algae-based supplements are an excellent option. Since fish get their omega-3s from eating algae, these supplements provide a direct, sustainable, and contamination-free source of marine omega-3s.

Conclusion: Making Informed Choices

The world of seaweed offers a diverse range of options for those seeking to incorporate more healthy fats into their diet. By understanding which seaweed is high in fatty acids, you can make informed choices based on your nutritional goals. While certain brown and red seaweeds stand out for their EPA and HUFA content, all edible varieties offer unique nutritional benefits. Whether enjoyed whole in a salad, as a seasoning, or taken as a supplement, seaweed and algae provide a sustainable pathway to obtaining the essential fatty acids vital for overall health. It's important to consume seaweed in moderation, as with any food, to maintain a balanced intake of nutrients, especially iodine. For those looking for an especially potent, direct source of EPA and DHA, algae-derived supplements are an excellent consideration. For more detailed scientific analysis on seaweed fatty acid profiles, refer to reliable nutritional research such as the study titled "Seaweeds as Valuable Sources of Essential Fatty Acids for Human Nutrition".

Frequently Asked Questions

Red seaweeds like Dulse (Palmaria palmata) and brown seaweeds like Wakame (Undaria pinnatifida) and Sargassum species are excellent sources of omega-3s, particularly EPA.

Most seaweeds contain some omega-3s, but the quantity and specific types vary significantly by species, environmental conditions, and season.

Vegans can consume various seaweeds in dishes or take algae-based supplements, which provide EPA and DHA directly.

Fish obtain their omega-3s from consuming algae, making algae the original source. Seaweed and algae-based supplements offer a sustainable, direct, and often purer source of EPA and DHA.

EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are important omega-3 fatty acids crucial for heart and brain health. They are abundant in certain seaweeds and algae, which are primary producers in the marine food chain.

While nutritious, seaweed contains high levels of iodine. Excessive consumption can lead to too much iodine intake, which can affect thyroid function. Moderation is key.

You can incorporate high-FA seaweeds like nori in sushi, wakame in soups and salads, and kelp in broths. Dulse flakes can also be used as a seasoning.

Not typically. While some green seaweeds like Ulva have a good total fatty acid content, studies suggest brown and red seaweeds often have a higher proportion of the more beneficial polyunsaturated fatty acids.