How to Read an Omega-3 Label

An omega-3 supplement label can tell you almost everything you need to know about the product, if you know which numbers to look at and which to ignore. Most people read the front of the pack, see "omega-3" and a large milligram figure, and assume they are getting what they need.

The useful information is on the back, in the nutritional panel, and most of it is smaller than the marketing text.

The Number That Matters: Individual EPA and DHA Per Serving

This is the single most important thing on any omega-3 label. Not "total omega-3." Not "fish oil concentrate." Not the weight of the capsule. You need the milligrams of EPA and DHA listed separately, per daily serving.

A product advertising "1000 mg omega-3" on the front might contain 400 mg EPA, 300 mg DHA, and 300 mg of other fatty acids. Or it might contain 900 mg ALA and 50 mg each of EPA and DHA. Those are completely different products for completely different purposes, but the front-of-pack claim looks identical.

We covered the ALA vs EPA vs DHA distinction in detail. The type of omega-3 determines whether you are meeting the intake conditions that matter.

Matching Your Label to the Health Claims

The EFSA-authorised health claims for omega-3 have specific intake thresholds:

• Heart function: 250 mg combined EPA+DHA daily
• Brain function: 250 mg DHA daily
• Normal vision: 250 mg DHA daily
• Blood triglycerides: 2,000 mg combined EPA+DHA daily
• Blood pressure: 3,000 mg combined EPA+DHA daily

Check your label against the specific claim you care about. If you are taking a supplement for heart function, you need the EPA+DHA combined figure to reach 250 mg per daily serving. If you are taking it for brain function, you need the DHA figure specifically to reach 250 mg.

A product can be adequate for the heart claim but insufficient for the brain claim if its DHA content is too low relative to its EPA content.

Serving Size vs Capsule Count

This is where labels get quietly misleading. Some products list their EPA and DHA figures per capsule. Others list them per "serving," where a serving is two or three capsules. If you read 500 mg EPA per serving without noticing that a serving is three capsules, you might take one capsule and get 167 mg.

Always check: what is the stated serving size, and how many capsules or scoops does that require? Then check whether the EPA and DHA figures are per serving or per capsule. These two numbers determine what you actually get each day.

We design our products so one capsule or sachet equals one serving. The arithmetic is straightforward. Not every manufacturer does this, and the difference matters when you are comparing per-day cost across products.

Source and Form

The label should tell you the source of the omega-3. Common sources include:

• Fish oil: Usually sourced from anchovy, sardine, or mackerel, containing both EPA and DHA in the natural ratios the fish accumulated from its diet.
• Algae oil: Typically produced from Schizochytrium, delivering DHA-dominant omega-3 with modest or no EPA content per capsule.
• Marine phytoplankton: Typically from Nannochloropsis, delivering EPA-dominant omega-3 with minimal DHA in a whole-cell powder format rather than extracted oil.
• Krill oil: Sourced from Antarctic krill, containing both EPA and DHA in phospholipid-bound form, but typically at lower doses per capsule than concentrated fish oil.
• Flaxseed oil or hemp oil: Contains only ALA, which is not a direct source of EPA or DHA and requires conversion at low rates.

If the label says "omega-3" without specifying the source, you cannot evaluate what form the fatty acids are in or whether the product meets your needs. We explain the source differences in our plant-based omega-3 guide.

Triglyceride vs Ethyl Ester Form

Fish oil and algae oil come in two chemical forms: triglyceride (TG) and ethyl ester (EE). The triglyceride form is the natural structure found in fish and algae. The ethyl ester form is produced during concentration and purification. Some research suggests triglyceride-form omega-3 has modestly better absorption, though both forms are effective.

Premium products often highlight "triglyceride form" or "rTG" (re-esterified triglyceride). If you do not see the form specified, the product is likely ethyl ester, which is cheaper to produce. This is a quality variable, not a dealbreaker. Both forms deliver EPA and DHA. The absorption difference is real but not dramatic.

Purity and Testing Claims

Look for third-party testing certifications or batch-specific purity data. For fish oil, relevant contaminants include mercury, PCBs, and dioxins. For algae-based products, the relevant panel is heavy metals (lead, cadmium, arsenic, mercury).

"Molecularly distilled" on a fish oil label means the oil has been purified through distillation to reduce contaminants. This is standard practice for quality fish oils, not a premium feature. For algae products, the cultivation method (closed photobioreactor vs open pond) is a more meaningful purity indicator than post-harvest processing claims.

What a Good Label Looks Like

A well-labelled omega-3 product tells you: the source species, the EPA and DHA content per serving listed separately, the number of capsules or scoops per serving, the chemical form (TG or EE), and either a third-party testing certification or a statement about batch-specific testing with documentation available on request.

If any of those elements are missing, the label is not giving you enough information to make an informed decision. We publish all of these for our own products — source species, per-capsule EPA or DHA figure, and batch-specific CoA results from third-party testing. That discipline came from trying to interpret competitor labels during product development: the gaps in other labels told us what ours needed to include.

This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Consult your GP or a qualified healthcare professional before starting any supplement.

Methodology and Disclosure

Phytality manufactures omega-3 supplements from microalgae. We have a commercial interest in supplement labelling transparency. EFSA intake conditions are cited from Commission Regulation (EU) No 432/2012. Label-reading guidance reflects standard supplement industry practice and regulatory requirements. The triglyceride vs ethyl ester absorption distinction reflects published bioavailability research. We have not named specific competing products.

Last reviewed: March 2026