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Salmon once a week, a spoonful of linseed oil in muesli, a handful of walnuts every now and then: for many, the topic of omega-3 is settled with that. However, the term covers various fatty acids, and not every source provides the ones that matter. Anyone looking to supplement in a targeted manner quickly faces the next question: Algae oil or fish oil? The answer depends less on which oil sounds better on the label and more on where the fatty acids originally come from, how reliably a source provides them, and in what form they exist. This article clarifies what foods actually contribute, why the fish source has changed in recent years, and what human studies show in a direct comparison of the two oils.
Contents
- EPA, DHA and ALA: Which omega-3 fatty acids your body needs
- Omega-3 foods: What fish, linseed oil and walnuts actually provide
- Fish as an omega-3 source: Why the calculation works differently today
- Algae oil or fish oil: What studies on bioavailability show
- Sensible omega-3 supplementation: Amount, omega-3 index and limits
- Conclusion: Omega-3 from the original source
- Briefly explained: The most important questions about algae oil and fish oil
EPA, DHA and ALA: Which omega-3 fatty acids your body needs
Omega-3 is not a single substance, but a family of fatty acids. Three of these are relevant for nutrition. Alpha-linolenic acid (ALA) is the short-chain, plant-based variant found in linseed oil, walnuts, or rapeseed oil. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are the long-chain forms that are actually the focus of the discussion regarding fish and algae.
The difference is not just chemical. In their review published in the journal Biomolecules in 2019, Gladyshev and Sushchik describe that EPA and DHA can only be synthesized to a significant extent by certain groups of algae. Animals, including humans, have only a comparatively limited ability to produce them from ALA.¹ Anyone who needs EPA and DHA is therefore fundamentally dependent on ingesting them directly.
The European Food Safety Authority (EFSA) specifies 250 mg of EPA and DHA per day as an adequate intake for adults.² The European Commission has authorized health claims for both fatty acids that are linked to precisely defined amounts:³
- DHA contributes to the maintenance of normal brain function (the beneficial effect is obtained with a daily intake of 250 mg of DHA).
- DHA contributes to the maintenance of normal vision (the beneficial effect is obtained with a daily intake of 250 mg of DHA).
- EPA and DHA contribute to normal heart function (the beneficial effect is obtained with a daily intake of 250 mg of EPA and DHA).
Omega-3 foods: What fish, linseed oil and walnuts actually provide
Plant-based omega-3 foods such as linseed oil, flaxseeds, chia seeds, or walnuts are good sources of ALA. However, they are only an indirect path for EPA and DHA, as the body must first convert the ALA, and this is only partially successful. Three studies show how much the results vary: in 2002, Burdge and Wootton found in the British Journal of Nutrition an estimated conversion of around 21 percent to EPA and around 9 percent to DHA in young women.⁴ In contrast, in 2005, Hussein and colleagues determined in the Journal of Lipid Research that in men, only about 0.3 percent converted to EPA and less than 0.01 percent to DHA.⁵ In the same journal in 2005, Goyens and colleagues arrived at around 7 percent for EPA and less than 0.1 percent for DHA in 29 women and men.⁶ A review by Baker and colleagues in 2016 concludes that the conversion to DHA in particular is limited in most people.⁷ Plant-based sources are therefore valuable, but do not replace a direct intake of EPA and especially DHA.
EPA and DHA are provided directly primarily by fatty fish. The German Nutrition Society (DGE) recommends eating fish once or twice a week and cites fatty varieties such as salmon, mackerel, or herring as suppliers of long-chain omega-3 fatty acids.⁸ Figures from the German Federal Institute for Risk Assessment (BfR) show how much of this actually reaches people in everyday life: people in Germany ingest between 127 and 295 mg of EPA and DHA per day through their normal diet.⁹ The range thus extends from significantly below the reference value of 250 mg to just above it.
Fish as an omega-3 source: Why the calculation works differently today
Fish is considered the omega-3 source par excellence. However, only a small part of the omega-3 is actually formed in the fish itself. The actual producers are microalgae, whose EPA and DHA are passed on through the food chain to microorganisms and ultimately to fish.¹ In this sense, fish is an intermediary storage point, not the origin.
For farmed fish, this has a practical consequence: it only contains EPA and DHA if they are in the feed. Traditionally, these come from fishmeal and fish oil from wild catches, the quantities of which are reaching their limits according to Gladyshev and Sushchik. If the fish oil in the feed is replaced by vegetable oils, the EPA and DHA content in the fish flesh drops significantly.¹
An analysis by Sprague, Dick, and Tocher, published in Scientific Reports in 2016, shows how significantly. They analyzed over 3,000 samples of Scottish farmed salmon. The content of EPA and DHA dropped on average from 2.74 g to 1.36 g per 100 g of fish between 2006 and 2015. To reach the weekly recommendation of 3.5 g of EPA and DHA from the international scientific society ISSFAL, one portion of salmon was sufficient in 2006, whereas by 2015, two were required.¹⁰
Added to this is the question of stocks. According to the UN Food and Agriculture Organization (FAO), only 62.3 percent of global marine fish stocks were fished within biologically sustainable limits in 2021.¹¹
For perspective, it should also be noted that the German Federal Institute for Risk Assessment does not consider omega-3 fatty acid supplementation necessary for healthy people who eat fish regularly.⁹ The EFSA states 250 mg of EPA and DHA per day as an adequate intake,² a value that the average diet in Germany does not always reach according to the BfR.⁹ Fish remains a good source. The question is rather how reliable it still is in everyday life when the same salmon provides significantly less today than it did a few years ago. Only a blood test will show whether your own supply is actually adequate.
Algae oil or fish oil: What studies on bioavailability show
Algae oil targets the source where EPA and DHA are created: directly at the microalgae, without the detour through fish. However, the decisive factor is not just the origin, but whether the body absorbs the fatty acids from the oil just as well.
An early study on this was conducted by Arterburn and colleagues. In 2008, they compared algae oil capsules with cooked salmon in the Journal of the American Dietetic Association and concluded that both can be considered equivalent sources of DHA.¹² A recent double-blind, placebo-controlled study by Bailey and colleagues, published in the International Journal of Molecular Sciences in 2025, monitored 74 adults over 14 weeks. Algae oil was compared with fish oil. The result: the absorption of EPA and DHA into blood lipids was statistically non-inferior for algae oil compared to fish oil.¹³ To be transparent: the authors of this study are mostly employed by dsm-firmenich, a manufacturer of algae oil. And "non-inferior" means equivalent, not superior. The current state of research provides nothing beyond that.
A common objection is that fish oil provides more EPA, while algae oil primarily provides DHA. This is true for many algae oils; even the oil used in the Bailey study contained significantly more DHA than EPA.¹³ However, this is not a general rule: how much EPA and DHA an algae oil contains depends on the algae strain and production process and can only be seen on the label of the respective product.
Beyond the source, the chemical form plays a role. In fish and algae, omega-3 fatty acids naturally exist predominantly as triglycerides. Ethyl esters, on the other hand, are a semi-synthetic form that arises during the industrial concentration of fish oil.¹⁴ In 2011, Neubronner and colleagues showed in the European Journal of Clinical Nutrition that at an identical dose, fish oil converted back into triglycerides raised the omega-3 index in 150 participants over six months faster and more strongly than the ethyl ester form.¹⁵ A possible reason is described by Dyerberg and colleagues (2010): the digestive enzyme pancreatic lipase splits ethyl esters less effectively than triglycerides. In their comparison, ethyl esters only achieved 73 percent of the bioavailability of natural fish oil.¹⁴ The ARTZT neuro algae oil is in triglyceride form. The fact that the form of a nutrient is a deciding factor can be seen not only with omega-3, but also when comparing vitamin D3K2 drops and capsules.
Then there is the origin: algae oil is obtained through fermentation, in the case of ARTZT neuro Omega 3 in closed stainless steel tanks rather than in the open sea. This makes production independent of catch quotas, fish stocks, feeding conditions in aquaculture, and environmental conditions in the ocean. For many, an ethical question also plays a role here: fish oil requires fishing, either directly or via the feed in aquaculture, which itself comes from wild catches.¹ Anyone who does not want to eat fish for this reason or because of their diet will find omega-3 without fish in algae oil. ARTZT neuro Omega 3 is suitable for a vegetarian diet; it is not strictly vegan, however, as it contains an egg ferment.
Sensible omega-3 supplementation: Amount, omega-3 index and limits
Whether one's own supply is adequate can be measured. The omega-3 index indicates the proportion of EPA and DHA relative to the fatty acids in the membranes of red blood cells and is determined via a blood test. It thus reflects intake over a longer period.¹⁶ In 2024, Schuchardt and colleagues evaluated globally available data in the journal Progress in Lipid Research: in most countries studied, the value is in the low to very low range. The authors classify values above 8 percent as desirable, which were only achieved in a few countries such as Finland and Iceland.¹⁷ (The 8 percent mark originally comes from research by Harris and von Schacky, who proposed the index as a metric in 2004.¹⁶) Once you know your own value, you can assess supplementation more precisely and check it again after a few months. In the study by Neubronner and colleagues, changes were measured after three and six months.¹⁵
Opinions differ on what is a sensible amount. EFSA sees no safety concerns for adults with an additional intake of up to 5 g of EPA and DHA per day.¹⁸ The BfR is more cautious, advising against a total intake of more than 1.5 g per day from all sources.⁹ A daily portion of ARTZT neuro Omega 3 provides 1.2 g of EPA and DHA; those who also eat fatty fish regularly can keep an eye on the total amount. For people with cardiovascular diseases, the European Medicines Agency has identified a dose-dependent increased risk of atrial fibrillation with omega-3 medications, highest at 4 g per day.¹⁹ Therefore, anyone with heart disease should clarify omega-3 supplementation with their doctor in advance.
Conclusion: Omega-3 from the original source
Algae oil or fish oil is ultimately less a question of better or worse, and more a matter of reliability and one's own diet. Plant-based foods primarily provide ALA, which the body only converts to a small extent. Fish provides EPA and DHA directly, but obtains them itself from algae through the food chain, and the amounts in farmed fish have dropped significantly in recent years. Algae oil draws directly from the original source of the food chain, and human studies show an absorption that is in no way inferior to that of fish oil.
The ARTZT neuro Omega 3 provides 2,000 mg of algae oil per daily portion with 1,200 mg of omega-3 (800 mg EPA, 400 mg DHA; as of October 2026) in triglyceride form, plant-based and without fish. This puts it above the quantities associated with the aforementioned authorized claims for DHA as well as for EPA and DHA. The oil is supplemented by natural vitamin E. Vitamin E helps protect cells from oxidative stress.
In the ARTZT neuro system, omega-3 is a building block of basic nutritional support, not a replacement for it. Together with vitamin D, which cannot be sufficiently synthesized by the skin in Germany for large parts of the year, as we explain in our article on vitamin D deficiency, it forms the foundation upon which nutrition, movement, and regeneration are built. Those who wish to cover this basic supply in one package can find the omega 3 together with the Vitamin D3K2 spray and iodine in our basic supply kit.
Briefly explained: The most important questions about algae oil and fish oil
Is algae oil just as good as fish oil?
In human studies, the body absorbs EPA and DHA from algae oil just as effectively as from fish oil. A double-blind study by Bailey and colleagues (2025) with 74 adults found an absorption of algae oil into blood lipids that was statistically non-inferior to fish oil.¹³ The question of algae oil versus fish oil is therefore primarily about the origin, form, and composition of the respective oil.
Does algae oil contain EPA or only DHA?
Many algae oils contain predominantly DHA, but this is not a fixed rule. The ratio of EPA to DHA depends on the algae strain and the manufacturing process. How much EPA and DHA a daily portion provides is shown in the nutritional information of the respective product.
Is linseed oil sufficient as an omega-3 source?
Linseed oil provides alpha-linolenic acid (ALA), but no EPA and DHA. The body can convert some EPA from ALA, but hardly any DHA. The conversion rate varies significantly depending on the person and measurement method: in a study on young women, it was around 21 percent to EPA and 9 percent to DHA,⁴ whereas in a study on men, it was only about 0.3 percent to EPA and less than 0.01 percent to DHA.⁵ Linseed oil is therefore a supplement, but does not replace a direct intake of EPA and especially DHA.
Why does farmed salmon contain less omega-3 today?
Fish hardly synthesize EPA and DHA themselves; they take them in through their diet.¹ In aquaculture, fish oil in feed has been increasingly replaced by vegetable oils. As a result, the content of EPA and DHA in Scottish farmed salmon fell from 2.74 g to 1.36 g per 100 g between 2006 and 2015.¹⁰
How much omega-3 is too much?
There are different benchmarks here. EFSA sees no safety concerns for adults with an additional intake of up to 5 g of EPA and DHA per day.¹⁸ The BfR is more cautious, advising against a total intake of more than 1.5 g per day.⁹ For people with cardiovascular diseases, the European Medicines Agency has identified a dose-dependent increased risk of atrial fibrillation, highest at 4 g per day; in these cases, supplementation should be clarified with a doctor.¹⁹
References
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DOI: 10.3390/biom9090485
URL: https://pmc.ncbi.nlm.nih.gov/articles/PMC6770104/ - EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA) (2010). Scientific Opinion on Dietary Reference Values for fats, including saturated fatty acids, polyunsaturated fatty acids, monounsaturated fatty acids, trans fatty acids, and cholesterol. EFSA Journal, 8(3), 1461.
DOI: 10.2903/j.efsa.2010.1461
URL: https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2010.1461 - Commission Regulation (EU) No 432/2012 of 16 May 2012 establishing a list of permitted health claims made on foods, other than those referring to the reduction of disease risk and to children's development and health. CELEX: 32012R0432.
URL: https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32012R0432 - Burdge, G. C. & Wootton, S. A. (2002). Conversion of α-linolenic acid to eicosapentaenoic, docosapentaenoic and docosahexaenoic acids in young women. British Journal of Nutrition, 88(4), 411–420.
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URL: https://pubmed.ncbi.nlm.nih.gov/12323090/ - Hussein, N., Ah-Sing, E., Wilkinson, P., Leach, C., Griffin, B. A. & Millward, D. J. (2005). Long-chain conversion of [13C]linoleic acid and α-linolenic acid in response to marked changes in their dietary intake in men. Journal of Lipid Research, 46(2), 269–280. DOI: 10.1194/jlr.M400225-JLR200
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DOI: 10.1038/srep21892
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Transparency note: This article was created with the help of AI and subsequently edited.
