By Declan Hallwood, Nutrition & Supplements Editor · Updated 26 June 2026
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Looking for the best vegan omega 3 supplement? Opti3 Omega 3 from Vegetology is one of the strongest contenders on the UK market, an algae-based supplement that delivers a high dose of EPA and DHA without a drop of fish oil. We tested it daily over six weeks and compared it against other big names in the vegan omega 3 space. Here's how it held up.
Vegan alternatives to fish-oil omega 3 are on the rise, and at first glance it can be hard to know which supplement to pick. If you're weighing up your options, Opti3 is well worth a closer look.
| Source | Microalgae (vegan) |
|---|---|
| EPA + DHA | ~800mg per serving (min 800mg) |
| Added vitamin | Vitamin D3 (cholecalciferol) |
| Capsules per bottle | 60 |
| Recommended serving | 2 capsules daily with food |
| Allergens | Free from gluten, sugar, wheat, dairy |
| Packaging | Biodegradable, recyclable sugar cane |
Opti3 is a British-made supplement from Vegetology, a company with a strong background in producing high-quality, environmentally-friendly supplements. We're big fans of Vegetology. Their ethos aligns closely with our own, and they clearly put a lot of work into both their products and their sustainable packaging.
We won't be biased towards them, though. If the capsules were impossible to swallow or tasted terrible, we'd tell it like it is.
The Opti3 Omega 3 supplement comes in a small bottle that is 100% biodegradable, recyclable and made from sugar cane, a genuinely thoughtful touch. Inside you get 60 capsules. Vegetology recommend taking two capsules a day with food for the best results. Personally, we think you'd still see benefits from just one a day, but that's our own preference.
At the recommended dose, a bottle lasts about a month, or roughly two months if you're happy with a single capsule a day.
Vegetology have kept the ingredients clear and simple. Each capsule contains a blend of oils for the omega 3, what they call the Opti3 Complex (microalgal oils, helianthus annuus oil and antioxidants). There's also cholecalciferol, which sounds intimidating but is simply vitamin D3.
The capsule itself is made from modified starch (a plant-based ingredient derived from cereals), vegan glycerol, carrageenan seaweed (used to replace gelatin) and sodium carbonate.
Nutritionally, you want a supplement with good levels of EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). These are the two most useful forms of omega 3 and are central to your general health and wellbeing.
Most independent organisations recommend between 250mg and 500mg of combined EPA and DHA per day. Opti3 provides around 800mg of combined EPA and DHA per serving. There are small fluctuations between batches, but it's always a minimum of 800mg, often higher.
How much omega 3 do you need?
Most health bodies suggest 250 to 500mg of combined EPA and DHA daily. With around 800mg per two-capsule serving, even a single Opti3 capsule comfortably covers the typical recommendation.
After taking two capsules a day for a month, we found no fishy aftertaste whatsoever. The capsule is faintly sweet, but it's barely noticeable. They go down quickly with a sip of water and leave no fishiness behind. Well done, Vegetology.
As with any supplement you plan to take long-term, cost matters. The thing to keep in mind with Opti3 is serving size: the recommended serving is two capsules, so a bottle lasts about a month at full dose.
However, many people will find a single capsule is more than enough, which effectively doubles the bottle's lifespan and brings the cost-per-day down considerably. It's worth deciding what your personal serving size will be before judging the value.
If you're after a quality vegan omega 3 that isn't full of rubbish ingredients and unpronounceable chemicals, Opti3 is a strong choice. Opti3 Omega 3 is one of the highest-quality supplements available on the UK market, from a company that genuinely prides itself on sustainability, quality and recyclable packaging. Not tied to a plant-based option? We put cod liver oil capsules and high strength fish oils side by side on EPA and DHA per serving, which is where algae oil usually costs more for the same numbers.
Yes. Opti3 gets its omega 3 from microalgae, the same source fish get their omega 3 from, rather than fish oil, so it's 100% plant-based and suitable for vegans and vegetarians.
Each serving of two capsules provides around 800mg of combined EPA and DHA (with a guaranteed minimum of 800mg, often higher). Most health bodies recommend between 250mg and 500mg per day, so even a single capsule covers the typical guideline.
No. After taking it daily for a month we found no fishy aftertaste at all. The capsule is faintly sweet but barely noticeable and goes down easily with water.
Yes. Opti3 is formulated to be safe for adults and children and is suitable for use during pregnancy. As always, check with your GP if you have specific concerns.
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