how vegans and vegetarians get enough omega-3

This is a guide to omega-3 for vegans and vegetarians, and anyone else who is concerned that they're not getting enough. Flexitarians, pescatarians, the merely curious: you're covered too.

what is omega-3?

Omega-3 is an essential nutrient, which means your body can't build it from scratch. It must come from your diet. [1]

Omegas are fatty acids, the basic building blocks of fats. There are several kinds of omega-3, but you only really need to know three:

• ALA, alpha-linolenic acid (found easily in plants)
• EPA, eicosapentaenoic acid
• DHA, docosahexaenoic acid

EPA and DHA are the ones responsible for most of the benefits and are used by your body directly, and they come from the sea.

You may have also seen omega-6 and omega-9, often bundled together as a 3-6-9 supplement. They're different fatty acids doing different jobs, and whether that bundle is a good idea is its own question. This guide is about omega-3.

What they mostly do is get built into things, rather than doing something to you. They're structural fats: they sit inside the membrane that wraps every cell you have, and the fats you eat change what those membranes are made from over time. DHA in particular collects where membranes have to stay flexible and carry electrical signals, which is why there's so much of it in the brain and in the retina of your eye.

That's also why it matters so much during pregnancy and early life. A baby's brain grows fastest from conception to around five years old, and the DHA it uses comes from the mother, first across the placenta and then through breast milk.

SUMMARY: omega-3 is essential, meaning you have to eat it. ALA comes from plants; EPA and DHA come from the sea and are the ones built into your cell membranes, especially in the brain and the eye.

what does omega-3 do?

There is a lot of established and ongoing research on omega-3. However, there are three benefits that scientists agree beyond a minimum amount.

At 250 mg of DHA a day, DHA contributes to normal brain function and vision.

At 250 mg of EPA and DHA combined, EPA and DHA contribute to the normal function of the heart.

At 2 g of ALA a day, ALA contributes to the maintenance of normal blood cholesterol levels. That's the plant one, and it's the easiest of the three to hit from food.

Beyond that, because omega-3 ends up in the membrane of every cell you have, it turns up in research on all sorts of things.

The heart benefit above is the agreed one, and it isn't the whole of the research. Reviews of the trial evidence describe a dose-response relationship, where more EPA and DHA tracks with better cardiovascular outcomes rather than there being a single threshold that switches it on. [23]

SUMMARY: the agreed benefits are brain function and vision at 250 mg of DHA a day, heart function at 250 mg of EPA and DHA together, and blood cholesterol at 2 g of ALA. Everything else is still being worked out.

what does omega-3 do about inflammation?

Something more specific than "it's an anti-inflammatory".

Inflammation is your immune system reacting to damage or infection, and it's a natural response that is supposed to be temporary. Switching it off again is an active job, and your body needs particular signalling molecules to do it, which it builds from EPA and DHA. [9][10]

EPA becomes a family called the E-series resolvins. DHA becomes the D-series resolvins, the protectins and the maresins. Researchers call the whole group specialised pro-resolving mediators, which is a long way of saying "the molecules that end inflammation". [9]

They do it two ways: they stop more white blood cells being called to the scene, and they nudge the clean-up cells already there, the macrophages, into clearing away the mess. [9] So this resolves inflammation rather than suppressing it. [8]

That's the mechanism and the measurements agree with it. An umbrella review pooled 32 separate meta-analyses of omega-3 supplementation in adults and found it lowered all three of the markers clinicians actually use to gauge inflammation: C-reactive protein, interleukin-6 and TNF-alpha. [20]

Put simply: give people more omega-3, and their inflammation levels drop. The shifts were modest rather than dramatic, and the trials pooled adults across all sorts of health states rather than healthy people going about their day.

This matters because chronic inflammation doesn't stay in one place. It simmers in the background, and it turns up alongside a long list of modern health struggles, including inflammatory bowel disease, cardiovascular disease, neurodegenerative disease and cancer. [8] Inflammation might not be the direct cause of all of them, and in some it's a consequence rather than a trigger, but it can make things worse.

Unfortunately, this kind of constant, low-grade inflammation is incredibly common today. Our modern environment is practically designed to trigger it. Between glitchy immune systems attacking healthy tissue, daily stressors like ultra-processed foods, lack of sleep, and constant stress, our gut microbiomes are being thrown completely out of balance.

Because modern life constantly triggers inflammation, getting enough omega-3s is one of the most practical ways we can help our bodies finally reset and find balance.

SUMMARY: modern life triggers inflammation which is linked to a range of diseases and conditions. Your body builds the molecules that end inflammation out of EPA and DHA.

what about oxidative stress?

Oxidative stress is the wear that comes from reactive molecules outpacing the body's own antioxidant defences. Researchers pooled 39 randomised trials covering 2,875 people to see whether omega-3 shifts it. Three markers moved: total antioxidant capacity went up, so did the activity of an enzyme called glutathione peroxidase, and malondialdehyde, a marker of oxidative damage to fats, went down. [21]

Three out of seven is a real result but also not a clean sweep.

SUMMARY: across 39 trials, omega-3 improved three markers of oxidative stress and left four unchanged.

are you getting enough?

If you eat oily fish twice a week, you almost certainly are. The NHS recommends two portions of oily fish per week, to comfortably cover the minimum recommendation. [11]

Unfortunately, most people in the UK don't manage it. [11] And if you don't eat fish at all, you're getting close to no EPA or DHA from food, because no non-marine plant source contains them.

For women who are pregnant or breastfeeding, the requirements are even higher. The DHA a baby uses comes from the mother through the placenta and then through breast milk. And if you already take a supplement, check which omega-3s are in it, because plenty of them are ALA only.

SUMMARY: two portions of oily fish a week covers it. Most people in the UK don't eat that, and if you eat none at all you're getting almost no EPA or DHA from food.

how can vegans and vegetarians get omega-3?

There are two routes. You can eat ALA from plants and rely on your body to convert it into the forms it actually uses, or you can take EPA and DHA directly from algae, which is the only plant source that supplies them ready-made.

The first route isn't really practical, so relying on a plant-based diet without a supplement isn't really an option. Here's why.

Most plant sources of omega-3, including walnuts, flaxseed, chia, hemp and soya, come almost entirely as ALA and contain almost no EPA or DHA. [1] Your body can theoretically convert some of that ALA into the other two, and it does, but it does a pretty poor job of it.

Reviews of ordinary diets put the ALA-to-EPA conversion at around 6%. [2] The conversion to DHA is even worse: somewhere between about 0% and 4% at the most generous end, and when researchers simply feed people more ALA for weeks or months, blood DHA doesn't reliably budge. [3][4]

Take the generous end and do the sum. To end up with the minimum recommendation of 250 mg of DHA, you would need roughly 6.25 g of ALA a day. Walnuts carry about 9.1 g of ALA per 100 g [5], so that's around 69 g of walnuts. Seven whole walnuts weigh about 28 g [5], so you're looking at roughly 17 walnuts a day, every day.

And that's the optimistic version, assuming optimal conversion. At the other end of the conversion range there is no number of walnuts that gets you there.

A modern diet makes it slower still. Omega-6 and omega-3 are processed by the same enzymes, so a diet heavy in omega-6 (which most Western diets are), means the two compete and conversion drops further. [2] That balance is the whole argument behind omega 3-6-9 supplements, which is a bigger topic.

SUMMARY: plant foods give you ALA, and your body converts only a little of it to EPA and very little to DHA. Hitting the DHA figure from walnuts alone would take about 17 a day, on the generous estimate.

what vegan foods contain omega-3?

Plenty, as long as ALA is what you're counting. [5]

Two tablespoons of ground flaxseed and about 700 g of edamame land in about the same place, which is useful to know before you build a week of meals around tofu.

There's a practical catch with flaxseed too. In a whole seed the oil is locked inside a hard coat and most of it goes straight through you, so grind it or buy it ground.

And none of these contain any EPA or DHA at all. Not a trace. They supply the raw material and your body has to do the conversion to EPA and DHA, which as we know is highly inefficient.

Which leaves an obvious question. If EPA and DHA only come from the sea, and you're not eating the sea, what exactly are your options?

SUMMARY: flaxseed and chia are the densest plant sources of ALA and walnuts are the easiest to eat. But none of them contain EPA or DHA, so they are not a reliable source.

where does the omega-3 in fish actually come from?

For most of the last few decades the answer to "how do I get EPA and DHA" has been one word: fish. Oily fish is the richest ordinary source of both, it's what the NHS recommendation is built around, and if you eat it a couple of times a week you genuinely don't need to think about any of this. [1][11]

For everyone else it has been a dead end, because there hasn't seemed to be anywhere else to go. Land plants don't make EPA or DHA. Fish do, so you eat fish.

Except fish don't make it either.

They get it the same way you would: by eating it. In coastal environments around the world, certain types of marine algae build EPA and DHA. Then, tiny creatures like plankton and krill eat the algae, which in turn get eaten by small fish like anchovies. Bigger fish then eat the small fish, and that's how omega-3 concentrates in the bodies of fish. By the time it reaches a salmon it has been through three or four steps in the food chain. [1]

So the omega-3 in fish oil was never really fish omega-3. It's algae omega-3 that has taken the long route.

That changes what algae is in this story. It isn't a vegan substitute for the real thing. It's where the real thing comes from, and it's the only source you can eat that makes EPA and DHA itself rather than borrowing them from something further down the chain. Every other plant food on that list above gives you ALA and asks your body to do the rest.

SUMMARY: fish don't make omega-3, they accumulate it from algae. Algae is the original source of the EPA and DHA in the sea, and the only plant-based source that supplies them directly.

does algae oil actually work as well as fish oil?

Going to the source is a tidy idea, and tidy ideas don't always survive a blood test. This one does. A randomised trial gave 32 adults either algal-oil capsules or portions of cooked salmon, both at 600 mg of DHA a day, and DHA rose by similar amounts in both groups. [6] A larger double-blind trial in 74 adults found microalgal oil statistically non-inferior to fish oil for both EPA and DHA. [7]

SUMMARY: in head-to-head trials, algae oil raised blood DHA about as well as salmon did, and matched fish oil on both EPA and DHA.

what about the fish?

Nutrition isn't the only thing to consider when choosing between fish and algae.

The ocean isn't clean. It is more polluted than it has ever been. Industrial pollutants like PCBs, dioxins and heavy metals don't break down easily, and because they dissolve into fat rather than water they concentrate as they move up the food chain. Fish absorb what they've eaten, and it ends up in the oil. A UK survey of 33 fish oil supplements found 12 that would have breached the EU dioxin limit introduced shortly afterwards. [12] Distillation reduces contaminants and there is some regulation in place to protect the public, but this doesn't fully remove the problem. Algae grown in a closed tank in purified water never comes into contact with these toxins in the first place.

The supply is under real strain. The share of the world's assessed fish stocks being fished within biologically sustainable levels has fallen from 90% in 1974 to 62.3% in 2021. [14] Most fish oil comes from Peruvian anchovy, and in 2026 Peru suspended its main season with only about a quarter of the quota caught. [15] Those numbers come from the FAO and from the fish oil industry's own trade body, not from us.

Learn more about the trouble with fish oil.

SUMMARY: fish oil starts in a polluted ocean and comes from a strained and potentially unsustainable supply.

what if you're pregnant or breastfeeding?

The need for DHA goes up and the source matters even more.

The NHS asks everyone for at least one 140 g portion of oily fish a week. But oily fish carry more pollutants than other seafood, so pregnant women or those planning a pregnancy are advised to limit their intake. The reason given is that those pollutants build up in the body and can affect a baby's development in the womb. [11]

Cod liver oils are even more of a concern. The NHS says avoid them altogether if you're pregnant or trying for a baby, because fish store vitamin A in their livers and too much retinol can harm an unborn baby. The overall ceiling is 1.5 mg of vitamin A a day from food and supplements combined, which is easier to reach than it sounds if you're taking cod liver oil. [11]

Algae oil is the ideal option here. It isn't a liver oil, so there's no vitamin A in it at all. It's grown in a closed tank, so there are no pollutants or heavy metals that might bioaccumulate.

SUMMARY: pregnant and breastfeeding women have an even higher requirement for DHA than the average adult, but are advised to refrain from large amounts of oily fish due to heavy metals and contaminants. Algae oil removes the risk of contaminants entirely.

so how do you actually hit those numbers?

The ALA target is easy. Two tablespoons of ground flaxseed carry about 2.7 g [5], which clears the 2 g figure between them. Walnuts, chia and rapeseed oil all help too.

EPA and DHA are the tricky ones. If you don't regularly eat the recommended two portions of oily fish per week, a supplement is the best option. Algae oil offers the best alternative to fish oil, but without the risk of contaminants.

Researchers use a measure called the omega-3 index: the share of the fatty acids in your red blood cells that are EPA and DHA. A review of 33 trials of DHA, EPA and cognition in children and young adults found studies were more likely to show an effect when the dose was at least 450 mg of DHA and EPA a day, and when it pushed the index above 6%. [22]

We've developed an algae-based omega supplement which helps you hit this target easily and safely.

SUMMARY: 250 mg of DHA a day for the brain and vision benefits, 250 mg of EPA and DHA together for the heart one, and 2 g of ALA for the cholesterol one. ALA is easy to get from plants. An algae based supplement is the best option for EPA and DHA.

can you take too much omega-3?

Not easily, as no formal upper limit exists, because the evidence isn't there to set one. European food-safety scientists concluded that supplemental EPA and DHA combined at up to 5 g a day doesn't raise safety concerns for adults, and EPA on its own up to 1.8 g a day. [19] For DHA alone the figure is about 1 g a day, which was reviewed again in 2026 and left where it was. [18]

The 250 mg target sits a very long way below that. You'd be taking twenty times the daily figure before you got near the level those reviews were even looking at.

There are still a couple of ceilings. In the UK the maximum allowed for DHA and EPA from algal oil is 3,000 mg a day in an adult supplement, and 450 mg a day in one intended for pregnant and breastfeeding women. [17] And at high doses, EPA and DHA combined at 2 to 6 g a day push LDL cholesterol up by about 3%. The same review adds that a rise of that size may not actually affect cardiovascular risk, but it's still a reason not to assume more is better. [19]

SUMMARY: no upper limit has been set, and 5 g a day of EPA and DHA combined is considered safe for adults. That's twenty times the 250 mg target, so overdoing it takes a lot of effort.

where can I get EPA and DHA without fish?

Algae oil, in practice. It's the only plant source that gives you both already made, so your body doesn't need to do a conversion step.

Ours is vegan omega-3 DHA and EPA from algae.

Whatever you go with, check a few things. Read the milligrams of EPA and DHA per serving rather than a combined "total omega-3" number, because total omega-3 can be almost entirely ALA. Buy it unflavoured. Check the date.

And keep eating the flaxseed and the walnuts anyway. ALA is essential in its own right, it carries its own agreed benefit, and the fibre and the rest of what comes with those foods is important too.

the bottom line

Plant foods aren't short of omega-3. They're short of the two kinds your body actually uses.

ALA is genuinely useful, easy to get, and has benefits for cholesterol at 2 g a day. What it won't reliably do is turn into EPA and DHA. Conversion runs at roughly 6% to EPA and somewhere between 4% and nothing to DHA, and there's no way to tell from the outside which end of that you're on.

So if you don't eat fish, the practical answer is something that already contains EPA and DHA. Algae is the one that does, and it's where the fish were getting theirs all along.