How to find the ultimate omega-3 supplement

Omega-3 fatty acids come in several forms. EPA and DHA are two of the best known and support, among other things, heart health, brain function and vision.

Omega-3 can be found in foods such as oily fish, including herring, sardines and mackerel. However, not everyone manages to get enough omega-3 through their diet. In that case, an omega-3 supplement can be a practical addition.

But how do you know whether an omega-3 supplement is good quality? And with so many options available, how do you tell the difference?

Not all products are created equal. Supplements can vary considerably in dosage, fatty acid form, purity, oxidation, processing and source. In this guide, we explain what to look for and how to recognise a high-quality omega-3 supplement.

What are the different forms of omega-3?

Omega-3 is an umbrella term for several fatty acids. The main forms are ALA, EPA, DHA and SDA. Here’s what sets them apart.

ALA

ALA is found in plant-based foods such as flaxseed, chia seeds, hemp seeds and walnuts. The body can convert ALA into EPA and DHA, but this conversion is limited.

EPA

EPA is mainly found in marine sources such as oily fish, shellfish and certain types of algae. EPA is an active form of omega-3.

DHA

Fish, seafood and algae contain DHA. DHA is also an active form of omega-3 and plays an important role in the brain and eyes.

SDA

SDA, or stearidonic acid, is less well known but still worth considering. It is an intermediate step in the conversion to EPA and is converted more efficiently than ALA. SDA is found in sources including hemp oil and Calanus oil.

How much omega-3 do you need?

There is no official recommended daily intake for EPA and DHA. However, many health organisations recommend 250–500 mg per day. In theory, you can get this amount through your diet. Oily fish such as salmon, herring, mackerel, sardines and anchovies are good sources. In practice, however, this can be more difficult. Not everyone eats fish every week, and the source and quality of the fish also matter. If you’re looking for a convenient and consistent way to supplement your intake, a pure omega-3 supplement can be a practical option.

What should you look for in an omega-3 supplement?

There isn’t one single feature that defines a high-quality omega-3 supplement. Dosage, fatty acid form, processing, oxidation and purity all matter. Below, we cover the key factors to consider when choosing an omega-3 supplement.

The amount of EPA and DHA

EPA and DHA are the active forms of omega-3. That’s why it’s important to look beyond the total amount of oil and check how much EPA and DHA the product actually provides.

This distinction matters: 1,000 mg of fish oil is not the same as 1,000 mg of EPA and DHA.

A good omega-3 supplement should therefore clearly state how much EPA and DHA you get per serving.

The EPA:DHA ratio

EPA and DHA are both active forms of omega-3, but they do not have exactly the same role. It can therefore be useful to consider the EPA:DHA ratio and whether it aligns with your goal.

For general health, a balanced ratio of EPA to DHA is often used. For more targeted support of omega-3 status, a higher EPA intake may sometimes be preferred.

Fatty acid form and absorption

Omega-3 comes in several different forms, and the form can affect how well it is absorbed.

• Triglycerides: This is the natural form of fat found in food. High-quality fish oil, cod liver oil and algae oil can be found in triglyceride form.
• Ethyl esters: This processed form is commonly found in concentrated fish oils. It allows for higher dosages, but is absorbed less efficiently by the body than triglycerides.
• Phospholipids: This form occurs naturally in krill oil. Phospholipids disperse well in water, contributing to efficient absorption.
• Wax esters: This form is specific to Calanus oil. Wax esters are digested slowly and release fatty acids gradually. Research suggests that EPA and DHA from Calanus oil are well absorbed, even at a lower dosage.

Processing

How an omega-3 oil is processed plays a major role in its quality. Many omega-3 oils are produced as concentrated extracts. To achieve higher levels of EPA and DHA, manufacturers may process the fatty acids using heat and chemical methods. This can involve converting them into ethyl esters and, in some cases, converting them back into triglycerides through re-esterification. These processes make higher concentrations possible, but take the oil further away from its natural form. If you prefer an oil that remains closer to its natural state, extra virgin cod liver oil and Calanus oil are examples worth considering.

A simple rule of thumb: the less intensive the processing, the closer the oil remains to its food-derived form.

How can you avoid oxidised omega-3?

Omega-3 fatty acids are vulnerable to oxidation. Exposure to oxygen, light and heat can cause the oil to deteriorate. Manufacturers therefore often add antioxidants such as vitamin E, tocopherols or rosemary extract. Some oils naturally contain compounds that help protect against oxidation. Calanus oil and krill oil, for example, contain the antioxidant astaxanthin. This helps keep the oil stable without additional antioxidants. Calanus oil even contains 20 times more astaxanthin than krill oil.

Lab testing and results

Want greater certainty about quality? Choose a brand that shares its test results. Pay particular attention to analyses for heavy metals, PCBs, dioxins and microbiological contamination. It is also worth checking the peroxide value and TOTOX score, which provide information about oxidation and freshness. Look for an omega-3 supplement that not only provides an effective dosage, but is also demonstrably pure, stable and independently tested.

The risk of contamination (and how to minimise it)

If you choose a marine source of omega-3, purity matters. Unfortunately, oceans can contain contaminants such as heavy metals, PCBs, dioxins and microplastics. Two questions are therefore particularly important:

1. Where does the oil come from? Norwegian fish oil is known for its high quality, thanks to clean coastal waters and decades of expertise.
2. Where does the source sit in the food chain? Larger, older fish accumulate more contaminants through bioaccumulation. Smaller species generally contain lower levels. Think anchovies and sardines, as well as sources such as algae, krill and Calanus.

Additional ingredients

Many products contain additional ingredients, such as seed oils used as carriers. Plant-based capsules can also contain modified starch or carrageenan. So don’t just look at the oil itself. Check the capsule and the full ingredients list too. A liquid format can often provide the simplest option.

Which omega-3 source is sustainable?

The source of your omega-3 affects not only its quality, but also its impact on the ocean. Fish oil can be sustainable, but this depends heavily on its origin, fishing pressure and certification. Krill oil is increasingly under scrutiny because krill are an essential food source for whales, penguins and seals. Look for certifications such as MSC or Friends of the Sea, and pay attention to where the oil comes from.

Algae oil is produced under controlled conditions and does not put pressure on marine ecosystems. Calanus is harvested low in the food chain and its population regenerates annually, making it another interesting sustainable source.

Algae oil or fish oil: which is better?

Fish obtain their DHA from algae, which makes algae oil seem like a logical source of omega-3. In practice, however, the picture is slightly more nuanced. Many algae oils are particularly rich in DHA and contain relatively little EPA. Fish and other marine sources often provide a broader spectrum of fatty acids, making them a more complex omega-3 source. That doesn’t mean algae oil is inferior. It simply means you should consider your goal and the composition of the product. If you’re looking for a clean, plant-based source of EPA and DHA, a high-quality algae oil can be an excellent choice. If you prefer a broader fatty acid profile that more closely resembles food, sources such as Calanus oil or cod liver oil may be a better fit.

When should you choose a broad omega-3 profile?

Some omega-3 sources contain other fatty acids and bioactive compounds in addition to EPA and DHA. Calanus oil, for example, provides a broad spectrum of fatty acids, including SDA, as well as policosanols and cetoleic acid. This makes it more of a food-based oil than an isolated EPA/DHA concentrate. This broader profile may be particularly interesting if you want to use omega-3 as part of your daily nutritional foundation rather than focusing solely on high doses of EPA and DHA.

Which omega-3 is right for your goal?

Looking for a broad, food-based foundation? An omega-3 with a wider fatty acid profile may be a good fit. NoordCode Ultimate Omega Formula contains Calanus oil with naturally occurring fatty acids such as EPA, DHA and SDA, alongside bioactive compounds such as astaxanthin. The oil is minimally processed and naturally stable thanks to the antioxidants it contains.

Want to supplement EPA and DHA more specifically? A high-dose source may be a better fit. NoordCode High EPA & DHA provides 1,200 mg EPA and 800 mg DHA from microalgae in triglyceride form. This makes it a plant-based source with a high dose of both EPA and DHA.

Want to understand the differences between these sources in more detail? Read our blog comparing the main sources of omega-3.

Checklist: how to recognise a high-quality omega-3 supplement

There is no single perfect omega-3 supplement for everyone. However, there are several characteristics that you’ll almost always find in a high-quality product:

• ✓ Clearly stated EPA and DHA dosage
• ✓ A well-absorbed fatty acid form
• ✓ Low oxidation values
• ✓ Independent lab testing
• ✓ Transparent sourcing
• ✓ Minimal processing
• ✓ No unnecessary additives
• ✓ Attention to sustainability