Omega-3 sources besides salmon include numerous fish, seafood, and plant-based options that provide essential fatty acids for cardiovascular, neurological, and inflammatory health. Whilst salmon is widely recognised for its omega-3 content, alternatives such as mackerel, sardines, herring, and anchovies often match or exceed its nutritional profile. Plant-based sources like flaxseeds, chia seeds, and walnuts offer alpha-linolenic acid (ALA), whilst algal oil supplements provide direct EPA and DHA for those following vegan diets. Understanding these diverse options enables individuals to meet omega-3 requirements regardless of dietary preferences, allergies, sustainability concerns, or budget constraints.

Why Omega-3 Fatty Acids Matter for Your Health

Omega-3 fatty acids are essential polyunsaturated fats that play crucial roles in maintaining cardiovascular, neurological, and inflammatory health. The three main types—alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA)—each contribute distinct physiological benefits. EPA and DHA, predominantly found in marine sources, are particularly important for heart health, cognitive function, and reducing systemic inflammation.

Research shows that adequate omega-3 intake supports cardiovascular health by helping to reduce triglyceride levels and may have modest effects on blood pressure in some individuals. Current NICE guidance (NG238) advises against omega-3 fatty acid compounds for cardiovascular disease prevention, though icosapent ethyl (a purified EPA) is recommended for specific high-risk adults under certain conditions (NICE TA805). DHA is a structural component of brain cell membranes and retinal tissue, making it important for cognitive development in infants and maintaining brain function throughout life.

Omega-3 fatty acids also modulate inflammatory responses by serving as precursors to anti-inflammatory mediators called resolvins and protectins. This mechanism may offer benefits for some individuals with inflammatory conditions, though omega-3 supplements are not a first-line treatment for conditions like rheumatoid arthritis. Some studies suggest potential roles in mental health, including possible benefits for depression and anxiety, but evidence remains preliminary and omega-3 supplements are not currently recommended by NICE for treating these conditions.

Whilst salmon is widely promoted as an excellent omega-3 source, many people seek alternatives due to dietary preferences, allergies, sustainability concerns, or cost considerations. Fortunately, numerous other foods provide substantial amounts of these essential fatty acids, ensuring that diverse dietary patterns can meet omega-3 requirements effectively.

Plant-Based Sources of Omega-3

Plant-based foods primarily provide alpha-linolenic acid (ALA), which the body can partially convert to EPA and DHA, though conversion rates are limited and highly variable between individuals—often lower than 5% for EPA and 2% for DHA. Despite this limitation, ALA itself offers cardiovascular benefits and can contribute meaningfully to overall omega-3 status, particularly when consumed regularly in adequate amounts.

Flaxseeds and flaxseed oil are among the richest plant sources of ALA, with just one tablespoon of ground flaxseed providing approximately 1.6 grams of ALA. Grinding flaxseeds enhances bioavailability, as whole seeds may pass through the digestive system intact. Flaxseed oil contains even higher concentrations but lacks the fibre and lignans present in whole seeds. It's best stored in the refrigerator and not used for cooking as heat damages the omega-3 content. These can be easily incorporated into smoothies, porridge, yoghurt, or baked goods.

Chia seeds offer approximately 5 grams of ALA per 28-gram serving (about two tablespoons), alongside substantial fibre, protein, and minerals. Their gel-forming properties when mixed with liquid make them versatile for puddings, overnight oats, or as egg replacements in vegan baking. Walnuts provide around 2.5 grams of ALA per 28-gram serving and make convenient snacks or additions to salads and breakfast cereals.

Hemp seeds contain approximately 1 gram of ALA per tablespoon, along with complete protein and gamma-linolenic acid (GLA), another beneficial fatty acid. Rapeseed oil is commonly used in UK cooking and provides modest ALA content—about 1.3 grams per tablespoon—making it a practical everyday option. Other sources include Brussels sprouts, spinach, and other leafy greens, though in smaller quantities. For those following plant-based diets, algal oil supplements derived from microalgae provide direct sources of EPA and DHA without relying on fish, offering a sustainable alternative that bypasses the conversion limitation of ALA.

Fish and Seafood Alternatives to Salmon

Numerous fish and seafood options provide excellent EPA and DHA content, often matching or exceeding salmon's omega-3 profile whilst offering variety, different flavour profiles, and sometimes more sustainable or economical choices. Mackerel is particularly rich in omega-3s, with Atlantic mackerel providing approximately 2.5–3 grams per 100-gram serving—comparable to or greater than salmon. It's widely available in the UK, relatively inexpensive, and can be enjoyed fresh, smoked, or tinned.

Sardines and pilchards (mature sardines) offer approximately 1.5–2 grams of omega-3 per 100-gram serving. These small, oily fish are typically consumed whole, providing additional calcium from their edible bones. Tinned sardines represent an economical, shelf-stable option that requires no preparation. Herring, whether fresh, pickled, or as kippers (smoked herring), contains similar omega-3 levels to sardines and has been a traditional component of British cuisine for centuries.

Anchovies, though often used as flavouring rather than main dishes, provide concentrated omega-3 content—approximately 2 grams per 100 grams. They're commonly available tinned in oil or salt and add umami depth to pasta dishes, pizzas, and salad dressings. Trout, particularly rainbow trout, offers around 1 gram of omega-3 per 100-gram serving and is often farmed sustainably in the UK.

Mussels, oysters, and other shellfish provide moderate omega-3 content alongside exceptional levels of vitamin B12, zinc, and selenium. Mussels contain approximately 0.7 grams per 100 grams, whilst oysters provide similar amounts. Crab and prawns offer smaller quantities but contribute to overall intake when consumed regularly.

When selecting tinned fish, options preserved in spring water or olive oil generally better preserve omega-3 content, as omega-3s can leach into other oils which are often drained away. For those concerned about sustainability, the Marine Conservation Society's Good Fish Guide provides UK-specific recommendations on environmentally responsible seafood choices.

NHS guidance advises that pregnant women, those planning pregnancy, and breastfeeding women should limit oily fish to 2 portions weekly due to potential pollutants, limit tuna to 2 fresh steaks or 4 medium tins weekly (due to mercury), and avoid shark, marlin, and swordfish completely.

How Much Omega-3 Do You Need Daily?

The UK does not have a specific recommended nutrient intake (RNI) for omega-3 fatty acids, but guidance from the Scientific Advisory Committee on Nutrition (SACN) and NHS recommendations provide practical targets. The general NHS advice for adults is to consume at least two portions of fish per week, including one portion of oily fish (approximately 140 grams), which typically provides around 2–3 grams of EPA and DHA combined weekly.

For those not consuming fish, achieving adequate omega-3 intake requires more deliberate planning. The European Food Safety Authority (EFSA) suggests that 250 milligrams of combined EPA and DHA daily supports normal heart function in adults. For ALA from plant sources, EFSA recommends an adequate intake of approximately 0.5% of total energy intake (roughly 1–1.5 grams daily for most adults).

Pregnant and breastfeeding women should aim for an additional 100–200 milligrams of DHA daily to support foetal and infant brain development. However, they should limit oily fish to 2 portions weekly, limit tuna consumption, avoid shark, swordfish and marlin completely, and avoid fish liver oils (which contain high levels of vitamin A that could harm the baby).

Individuals with specific medical conditions may have different requirements. NICE recommends icosapent ethyl (a purified EPA) only for certain high-risk adults with elevated triglycerides and established cardiovascular disease (TA805). Higher-dose omega-3 supplementation should only be undertaken under medical supervision, as it can increase bleeding risk, particularly in those taking anticoagulant medications such as warfarin or direct oral anticoagulants (DOACs).

Practical considerations for meeting omega-3 requirements include varying your sources throughout the week—combining oily fish, plant-based ALA sources, and potentially algal supplements for vegans. Those with fish allergies, strict dietary restrictions, or concerns about marine pollutants should discuss supplementation options with their GP or a registered dietitian. When choosing supplements, look for products that specify EPA and DHA content clearly. If you experience any suspected side effects from supplements, report them through the MHRA Yellow Card Scheme. Regular consumption of diverse omega-3 sources, rather than sporadic high doses, provides the most consistent health benefits whilst minimising potential adverse effects.

Frequently Asked Questions