Omega-3 test: what it measures, how long it takes and what you get out of it

About half of Norwegian adults take supplements.[source pending] Many of them take omega-3. What they rarely know is whether what they take makes any difference to what is in their blood. An omega-3 test is the simplest way to find out.

What an omega-3 test is

An at-home omega-3 test is a fatty-acid test that uses a dried blood spot. You prick your finger, let a few drops fall on a filter card, let it dry and post it to a laboratory.[source pending] The laboratory analyses the fatty acids in the sample and sends you a report.

It takes about ten minutes at home. Results usually arrive after a few weeks. Read the sampling guide before you start and it goes more smoothly.

What you learn

The report usually shows three things:

• The Omega-3 Index. EPA and DHA as a share of the fatty acids in red blood cells.[source pending]
• The omega-6:3 ratio. How much omega-6 there is for each part omega-3, a measure of overall fat balance.
• A broader fatty-acid profile. The distribution of different fatty acids, often with the AA:EPA ratio as well.

Because red blood cells live for about four months, the numbers reflect your diet over the last few months, not just last week.[source pending] One fish dinner the day before the test moves very little.

What you don't learn

The test shows where you are today. Why the numbers look the way they do, and what to do about them, we work out together.

Intake is not the same as level

It is easy to assume two capsules a day give a particular result. But content and absorption vary between products and between people,[source pending] and the rest of your diet, especially how much omega-6 you get, affects the balance. The calculator below gives a rough estimate of what you get from food. Only a test shows what has ended up in your blood.

When testing makes sense

• You already take omega-3 and want to know whether it shows up in your blood.
• You have changed your diet, for example more fish, and want to see whether anything moved.
• You want a baseline before deciding what to do.

A test is most useful when it is repeated. The first shows where you are. The next, about 120 days later, shows whether your changes moved anything.

EPA, DHA and the authorised claims

The EU has authorised the claim "EPA and DHA contribute to the normal function of the heart" with a daily intake of 250 mg EPA and DHA, and "DHA contributes to maintenance of normal brain function and normal vision" with 250 mg DHA a day.[European Commission 2012]Official Journal of the European Union · 2012Commission Regulation (EU) No 432/2012 establishing a list of permitted health claims made on foods, other than those referring to the reduction of disease risk and to children’s development and healthEuropean Commission↓ eu-432-2012↗ eur-lex.europa.eu ## Next step

Not sure a test is right for you? Take the free 2-minute check. It asks no health questions, and it tells you straight whether testing is worth it.

Sources

1. [source pending] Source needed: national survey data on supplement use among Norwegian adults
2. [source pending] Source needed: validation of dried blood spot fatty-acid analysis against venous samples
3. [source pending] Source needed: original definition of the Omega-3 Index (EPA + DHA as % of red blood cell fatty acids)
4. [source pending] Source needed: red blood cell lifespan (~120 days) and how fast membrane fatty acids change
5. [source pending] Source needed: review discussing the usefulness and limits of the omega-6:3 ratio as a marker
6. [source pending] Source needed: study on how much EPA+DHA content and absorption vary between supplements and between people
7. European Commission. Commission Regulation (EU) No 432/2012 establishing a list of permitted health claims made on foods, other than those referring to the reduction of disease risk and to children’s development and health. Official Journal of the European Union (2012).