Vegan Omega-3 Fatty Acids: A Concern?

Vegan Omega 3 – How to meet your needs

Each fatty acid performs important functions in the body. Omega-3 fatty acids are polyunsaturated fatty acids. They cannot be produced in the body or can only be synthesized via extensive metabolic pathways. However, not all of them are found in plant foods. This begs the questions: Can you meet your requirements of omega-3 fatty acids on a vegan diet? What are good vegan omega-3 sources?

Among other things, omega-3 fatty acids can reduce inflammatory processes in the body. They are therefore considered an important factor in maintaining health and reducing health risks, and scientific studies indicate potential in the treatment of various diseases (Troesch et al., 2020; Choi et al., 2021).

The omega-3 fatty acid alpha-linolenic acid (ALA) is considered essential because it is not produced in the body and therefore must be obtained from the diet. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) can be synthesized from ALA in the body, but only to a limited extent.

Functions

Omega-3 polyunsaturated fatty acids are part of cell membranes and increase their fluidity. Every cell in the body is coated with a membrane that separates the inside of the cell from the outside and maintains its mobility with the help of these fatty acids. High concentrations are found in the brain and nerve cells. The two fatty acids are also involved in the development of the brain and retina during the growth phase.

Omega-3 and omega-6 fatty acids play an important role as substrates for tissue hormones (metabolic mediators) during inflammatory processes. Arachidonic acid (ARA) is an omega-6 fatty acid that has been shown in cell experiments to have both anti-inflammatory and pro-inflammatory potential. ARA in its active form is found only in foods of animal origin. It is also formed in the body from its precursor, the essential linoleic acid (LA). LA is the predominant omega-6 fatty acid found in plant foods. Only a small amount of ALA is converted to ARA in the body (about 0.2 %) (Harris et al., 2009). ARA and LA both have important functions in the body.

ALA is mainly found in plants. Therefore, ALA can be considered the “vegan omega-3 fatty acid”. It acts primarily after conversion to the biologically active forms.
The metabolites of EPA and DHA have anti-inflammatory effects. They dilate blood vessels, regulate blood pressure and can have a positive effect on blood lipid levels. They can replace part of the ARA in the membranes of inflammatory cells.

Bioavailability

As you have already learned, the omega-3 fatty acid ALA found in plants can be converted to EPA and DHA in the body. However, this process is very limited, with a conversion rate of < 10 % to EPA and < 1 % to DHA. This rate is highly variable and depends on age, gender, genetics, disease, and diet, among other factors. Women have a higher conversion rate, which may be due to fetal and infant care. It is also important to get enough energy, protein, and micronutrients such as biotin, calcium, copper, magnesium, zinc, and pyridoxine. A diet very high in ALA or ARA can reduce the conversion rate (Innes and Kalder, 2020).

Linoleic acid, a plant representative of omega-6, is converted to arachidonic acid by the same enzyme system as ALA. Therefore, a high intake of omega-6 can reduce the conversion of ALA to EPA and DHA. Thus, with a low intake of omega-3 fatty acids, a high intake of omega-6 fatty acids may further worsen the status. However, the focus should be on getting enough omega-3 fatty acids in the first place. If you consume sufficient DHA and EPA from algae oils you do not need not worry about excessive intake of omega-6 fatty acids. Since these also have beneficial health effects, their intake should not be overly restricted since an excessive intake of omega-6 fatty acids is unlikely, especially on a vegan diet.

Good to know: In practice, LA intake does not appear to have a relevant effect on inflammation levels and other health markers. To reap the health benefits of omega-3 fatty acids, it’s important to get enough of EPA and DHA. Have you heard anything to the contrary? While the assumption that omega-6 fatty acids are pro-inflammatory is not incorrect, the conclusion that they are detrimental to health has not been proven in practice (Arterburn et al., 2006; Johnson and Fritsche, 2012; Rett and Whelan, 2011).

The bioavailability of EPA and DHA, like the conversion rate, is subject to wide individual variation. It also appears to depend on age, nutritional status, genetics, and the rest of the diet (von Schacky, 2019; Sparkes et al., 2020).

For those looking for a good omega-3 supplement, most studies show that DHA and EPA in triglyceride form are more bioavailable than in ethyl ester form. In addition, concurrent fat intake enhances absorption. For example, one study showed a threefold higher bioavailability of EPA and DHA in ethyl ester form in a meal with 55 g of fat compared to a low-fat meal with 8 g of fat (Lawson and Hughes, 1988; Schuchardt and Hahn, 2013). The large variability in conversion and bioavailability makes it difficult to define dietary requirements and intake recommendations.

The active form of EPA with anti-inflammatory effects is found in cold-water fish such as herring, mackerel or sardines. Like humans, fish are unable to synthesize EPA themselves and get the fatty acid from algae. Fish, as the bottom of the food chain, are already relatively polluted with contaminants such as heavy metals. The problem of overfishing of many marine animals and the ethical aspects are additional reasons for vegans to avoid fish and therefore relying on other vegan omega-3 sources.

Needs

Nutrition organizations give different recommendations for intake. The German Nutrition Society (DGE) provides reference values of 2.5 % linoleic acid and 0.5 % α-linolenic acid (estimated) from daily energy intake (DGE, 2016). The 0.5 % of α-linolenic acid is approximately 1.3 g for an energy intake of 2300 kcal and can be ingested with, for example, a heaping teaspoon of flaxseed (coarsely ground and/or soaked). The “estimated value” for ALA means that “there are still uncertainties, e.g. due to variations in measured values or too few (adequate) results of studies in humans” and therefore no certain requirement can be derived.

Infants and young children have an additional need for omega-3 fatty acids due to their brain development. In addition, their ability to synthesize omega-3 fatty acids is not fully developed, which can lead to deficiencies. The DGE recommends a daily intake of 200 mg of docosahexaenoic acid for pregnant and lactating women. However, an additional intake of EPA also appears to be important, since only a limited amount of DHA is converted back to EPA (about 4–11 %) (Greenberg et al., 2008).

For other groups of people, the DGE does not currently provide official intake recommendations. The minimum 70 g of fatty fish mentioned in the dietary recommendations can provide about 150 mg of EPA and DHA per day. EFSA recommends that adults consume 250 mg of EPA + DHA per day, and nutrition organizations in other countries recommend between 450 and 667 mg of EPA + DHA per day (Kris-Etherton et al., 2009).

In one study, Walker and colleagues calculated that approximately 2 g of EPA + DHA per day would be required to increase existing low levels to 8 % within about three to four months. However, individual responses to supplementation vary widely.

There are specific recommendations for the treatment of certain disease. For example, intakes above 3 g EPA + DHA are considered necessary for the treatment of coronary heart disease (Skulas-Ray et al., 2019).

EFSA concluded from the available literature that a minimum daily intake of 5 g EPA + DHA and 1.8 g EPA alone from supplements does not pose a health risk. The scientists could not to derive a tolerable upper intake level (UL) because the doses used in the studies did not cause any adverse effects. High intakes could theoretically increase the risk of spontaneous bleeding (EFSA, 2012).

Deficieny

A deficiency in one of the essential fatty acids can manifest in

• scaly skin rash
• reduced growth in infants and children
• increased susceptibility to infection
• poor wound healing

According to EFSA, the following health claims are permitted for omega-3 fatty acids (EFSA, 2011)

• ALA helps maintain normal blood cholesterol levels (2 g/d).
• DHA helps maintain normal vision (250 mg/d).
• DHA helps maintain normal brain function (250 mg EPA + DHA/d).
• DHA helps maintain normal blood triglyceride levels (2 g/d).
• EPA and DHA help maintain normal heart function (250 mg EPA + DHA/d).
• DHA and EPA help maintain normal blood pressure (4 g EPA + DHA/d).

With regard to the healthy development of children, EFSA considered the following statements to be substantiated

• DHA contributes to vision development in young children (100 mg DHA/d or 0.3 % of total fatty acids are DHA).
• Maternal intake of docosahexaenoic acid (DHA) during pregnancy and lactation contributes to normal brain development in the fetus and breastfed infant (additional 200 mg DHA/d).
• Maternal intake of docosahexaenoic acid (DHA) during pregnancy and lactation contributes to normal eye development in the fetus and breastfed infant (with an additional 200 mg DHA/d).

An insufficient intake of omega-3 fatty acids has a negative effect on these functions and is associated with an increased incidence of various diseases. The protective effects of omega-3 fatty acids EPA and DHA on the following conditions are discussed

• cardiovascular health
• cognitive abilities
• inflammatory diseases (rheumatism, arthritis)
• asthma
• type 2 diabetes mellitus
• neurological diseases (e.g. dementia, Alzheimer’s disease)
• depression
• recovery after physical activities
• support of medical cancer treatment

(Lanchais et al., 2020; Troesch et al., 2020; Avallone et al., 2019; Kostoglou-Athanassiou et al., 2020; Innes et al., 2020).

A recent review of existing studies examining the association between omega-3 intake and mortality risk found that the highest blood concentrations of EPA, DHA, and DPA were associated with a significantly lower risk of death than the lowest concentrations (Harris et al., 2021).

What exact functions and potential for disease prevention and treatment each fatty acid has is the subject of ongoing research. No clear conclusions can yet be drawn. There is evidence that EPA and not DHA is responsible for cognitive improvements (Patan et al., 2021; van Lent et al., 2021). One study also showed differential effects of EPA and DHA on sleep (Patan et al., 2020).

The results of the studies are sometimes difficult to interpret because the study design varies widely, the doses are sometimes low and variable, the subjects’ baseline levels vary, and it is unclear whether the doses used during the course of the study were even enough to reach adequate levels.

Occurrence

Now that you know the many potential benefits of omega-3 fatty acids, you may be wondering how you can benefit from them on a vegan diet. Vegan omega-3 sources and their levels of ALA and LA are listed in Table 1.

Table 1: Polyunsaturated Fatty Acid Content of Plant Foods (Koerber et al., 2012. Adam, 2007. Cunnane et al., 1993).

But what about EPA and DHA? The intake of the “vegan omega-3 fatty acid” ALA alone is probably not enough for most people (Schuchardt and Hahn, 2013; Arterburn et al., 2006). But don’t worry: you can get your omega-3s if you are vegan.

The main source of omega-3 fatty acids, EPA and DHA, is marine life. Those who eat a mixed diet get them primarily from fatty fish such as salmon, mackerel, and herring. What many people do not know is that fish cannot synthesize EPA and DHA themselves, but get them from algae. Fish, being at the bottom of the food chain, are already relatively contaminated with, for example, heavy metals. So why not eat seaweed while you’re at it?

One type of algae that is rich in EPA and DHA is called Schizochytrium algae. It is a microalgae and about 40 % of the oil extracted from it is omega-3 fatty acids in the form of EPA and DHA (Doughman et al., 2007). The oil from this algae is approved as a novel food in the EU and can be used in dietary supplements, fortification of various foods and in baby food (NDA, et al., 2020). The microalgae Ulkenia sp. is also used to fortify some foods with DHA (minimum content 32 %) (European Commission, 2009). Depending on the production methods, the production can have more or less environmental impact.

There are several ways to integrate algae oil into your diet: You can buy the oil itself in liquid form, vegetable oils fortified with it, and omega-3 supplements in capsule form. Dosages and other ingredients vary. In some countries, you can find food products fortified with the omega-3 fatty acids. Research is also being conducted on other plant sources that can provide a sustainable supply of EPA and DHA (West et al., 2021).

Due to the double bonds in the fatty acids, the oil is susceptible to oxidation and can easily become rancid, which can be harmful to health. By using high quality oils, certain production methods and adding antioxidants, manufacturers can extend the shelf life. You can take care to store the oil or capsules in a dark, cool place and not for too long. Capsules can be stored in the freezer.

Status in Vegans

The overall intake of omega-3 fatty acids is similar in different population groups, regardless of dietary form. Differences are seen in the different forms of fatty acids. The intake of ALA is similar among vegans, vegetarians, and mixed dieters. In contrast, only the latter groups consume significant amounts of EPA and DHA (Saunders et al., 2012).

As a result, the breast milk of vegan women contains significantly lower concentrations of EPA and DHA than that of  women eating a mixed diet. As a result, blood concentrations in infants are also lower. Negative effects on cognitive development have not been demonstrated (West et al., 2021; Sanders and Retty, 1992).

You can have a blood test done to determine your omega-3 status. According to current research, the best parameter for this is the omega-3 index in the erythrocytes. It should be at least 8 % (von Schacky, 2014).

Vegans show lower blood levels of long-chain polyunsaturated fatty acids compared to non-vegans (Rosell et al., 2005). However, most mixed-food eaters also have an inadequate status, and their omega-3 index is often lower than the recommended 8 % (Stark et al., 2016; Sarter et al., 2014). How many people do you know who regularly eat (fatty) fish at least twice a week? Probably not many. Therefore, it is reasonable to assume that supplemental DHA and EPA may be beneficial for people who consume little or no fish.

How Much Omega-3 Should Vegans Take?

Research shows that vegetarians and vegans may benefit from DHA and EPA intake from the mentioned algae oils. After several weeks of intake, their initially inadequate DHA and EPA intake was significantly improved (Geppert et al., 2005; Craddock et al., 2017; Sarter et al., 2014).

The doses required to achieve adequate levels cannot be given. Responses to supplementation varied widely across studies, depending on, among other things, the levels before supplementation, digestion, absorption, transport, uptake into target tissues, metabolism after storage, and the rate of conversion of ALA to the omega-3 derivatives. Therefore, no general recommendations can be made (Geppert et al., 2005). In addition, it is important to consider whether the omega-3 fatty acids are to be used primarily as a preventive measure or to improve, for example, the presence of inflammatory diseases, increased cardiovascular risk or other diseases. If the latter is the case, higher doses (probably at least 2 g per day) are most likely required (AbuMweis et al., 2021).

Therefore, you should first determine your status using the Omega-3 Index. Depending on how good your status is, you can choose the starting dose. Test your status again after about 3 months and adjust the dose from there. We recommend that you discuss the dosage with your doctor. If you are taking any medications and/or have any medical conditions, it is important to include these.

Summary

There are several types of omega-3 fatty acids. Plant foods contain alpha-linolenic acid (ALA), which can be considered the “vegan omega-3 fatty acid”. It can be converted to EPA and DHA in the body. However, the conversion rate is low, and usually the intake of ALA is not sufficient to obtain the health benefits of EPA and DHA. Therefore, in addition to regular consumption of ALA-rich foods such as flaxseed, hempseed, chia seed, walnut oil, canola oil, and soybean oil, it is recommended to consume vegan DHA- and EPA-rich oils, which are currently derived from certain microalgae.

In summary, vegans can get the essential omega-3 fatty acids in amounts needed to meet their requirements. The Omega-3 Index can be used to monitor your status. With regular monitoring, you can determine the amount of vegan omega-3 you need to get through supplements.

The content of this article cannot and should not replace an individual vegan nutrition consultation. Search the International Directory for Vegan Nutritionists to find an expert in your area, either locally or online.

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Medical Disclaimer and Other Notes

Medical Disclaimer

Like any science, medicine and related disciplines are subject to constant development. Research and clinical experience expand our knowledge, especially with regard to treatment and therapy. Insofar as a recommendation, dosage, application, etc. is mentioned in the information provided, you may trust that we have taken great care to ensure that this information corresponds to the state of knowledge at the time of completion of the work. However, no guarantee or liability can be assumed for such information. You are required to check them carefully yourself and act on your own responsibility. Furthermore, our recommendations and advice are in no way intended to replace medical advice, diagnosis or treatment in the case of an existing illness - it is not a therapy. You should therefore never use the information we provide as your sole source for making health-related decisions. In case of complaints, medical advice should be sought in any case.