Clinic appointment
Omega-3 and Omega-6 Test
The omega-3 and omega-6 fatty acids in your red blood cells, and the balance between them.
- Doctor-reviewed results
- Laboratory analysis
- 3 to 5 working days from lab receipt
- No fasting required
What’s included
1 marker measured
Omega-3 / omega-6 balance
The balance of omega-3 and omega-6 fats measured inside your red blood cells.
Overview
Fatty acids measured inside red blood cells reflect your intake over the past few months rather than what you had for dinner, so this is a stable picture of the fats in your diet. People test it when they eat little oily fish, take a fish oil supplement and want to know whether it is doing anything, or follow a vegan diet and are relying on algae oil.
Measuring fatty acids inside red blood cells reflects your intake over the past few months rather than what you had for dinner, which is why it is a more stable picture than a plasma measurement. Omega-3 comes mainly from oily fish and supplements, omega-6 from vegetable oils and processed food, and the ratio between them is what most people are asking about. It is a diet and supplement measurement rather than a medical test, and the doctor's note explains what the numbers reflect.
Who this is for and who it isn’t
Who it’s for
- Adults aged 18 and over
- Anyone who eats little oily fish and wants to know where they stand
- People taking a fish oil or algae supplement who want to see the effect
Who it isn’t for
- This is a dietary measurement rather than a medical test, and it will not explain a symptom. It is not a heart risk assessment either: cholesterol, blood pressure, blood sugar and family history are what UK guidance is built around, and none of them is measured here. There is also no agreed target level in UK clinical guidance, so read the result as a picture of your intake rather than as a score to chase.
- Anyone with a new, severe or worsening symptom: contact your GP or call NHS 111. A test you buy today is not a substitute for being examined.
Common reasons people choose this test
- Eating little or no oily fish
- Taking a fish oil or algae supplement and wanting to see the effect
- Following a vegan or largely plant-based diet
- Wanting to see the effect of eating more oily fish
- Wanting a baseline before changing what you eat
These are reasons people choose to test, not signs that something is wrong. A result is one part of a picture your doctor puts together with your history and an examination.
What your result looks like
Every result is shown with the unit and the reference range exactly as the laboratory reported it, with the doctor’s note underneath.
- Omega-3 / omega-6 balance▼ Low
- Result
- 3.9 % of total fatty acids
- Range
- Omega-3 index >8%
| Marker | Result | Units | Range | Flag |
|---|---|---|---|---|
| Omega-3 / omega-6 balance | 3.9 | % of total fatty acids | Omega-3 index >8% | ▼ Low |
Doctor’s note (example)
The omega-3 index is at the lower end, which reflects intake over the past few months rather than the last few days. This is a dietary picture rather than a medical finding, and a dietitian or your GP is the right place to discuss what to do with it.
Values above are examples. Your report shows your own results with the laboratory’s units and reference range for your age and sex, reviewed, signed and released by a GMC-registered doctor.
How it works
- You book your appointmentA trained clinician takes your sample at one of our London clinics. Nothing to do at home.
- The clinician takes your sampleA single clinic blood draw by a trained clinician
- The laboratory analyses itYour sample is processed for the measurements included in this test. Lab processing typically takes 3 to 5 working days from receipt of your sample.
- A doctor reviews and releases itA GMC-registered doctor reads every result and signs the report before it reaches you.
- Sample
- Clinic blood draw
- Preparation
- No fasting required
- Who it's for
- Any sex · ages 18+
How to prepare
What we can and can’t tell you
The reference range beside each result is the laboratory’s own. A result in range is not a clean bill of health and a result outside it is not a diagnosis. Most ranges cover about 95% of healthy people, so about 1 in 20 healthy people fall just outside any one range. No test result replaces an examination or your own doctor’s judgement, and none of these panels is a cancer screening programme.
Read the full note
The reference range printed beside each of your results is the laboratory's own, and it is the range that applies to your result. We do not apply a second range of our own, and we do not tell you that a result the laboratory reported as normal is nonetheless too low or too high. If you see a claim elsewhere that your result ought to sit inside a narrower band than the one the laboratory printed, treat it with caution and ask your doctor.
Some assays cannot give an exact figure above or below a certain point, and those results are reported the way the laboratory sends them, for example as a value greater than a stated number. A result in range is not a clean bill of health, and a result outside a range is not a diagnosis: most reference ranges are set to cover about 95% of healthy people, so some healthy people fall just outside them. No blood test replaces an examination, a scan or your own doctor's judgement, and none of these panels is a screening programme for cancer.
If you have a symptom that is new, severe, or getting worse, contact your GP or NHS 111 rather than waiting for a test result. In an emergency call 999.
Frequently asked questions
Do I need to fast?
No. Because the measurement is made inside red blood cells rather than in plasma, it reflects months of intake and a recent meal makes no difference.
How long after starting a supplement should I test?
About three to four months. Red blood cells live roughly that long, so anything sooner is still mostly showing your previous pattern.
Does the ratio matter more than the individual numbers?
The balance between omega-3 and omega-6 is what most people are interested in, since western diets tend to be heavy on omega-6 from vegetable oils. Your report shows the laboratory's result, and the doctor's note explains what it reflects about your diet.
Will this tell me whether to take fish oil?
It tells you where your levels sit. Whether to supplement, and with what, is a decision to make with your GP or a registered dietitian, particularly if you take blood-thinning medicines.
How long do results take?
The laboratory typically takes 3 to 5 working days from receiving your sample. This does not include kit delivery, sample collection or return postage. A doctor reviews your results before they are released.
Can I choose a home kit or a clinic?
This test is a clinic blood draw, as it needs a venous sample for accuracy. We arrange a convenient appointment for you.
Is a doctor involved?
Yes. Every result is reviewed by a GMC-registered doctor who signs it off and explains what it means and what to do next.
Is it confidential?
Your results are available through your secure patient portal. Our privacy policy explains how your information is handled and when it may be shared to provide your care.
What happens to my sample and results?
Your sample is analysed at a UKAS-accredited laboratory (ISO 15189). A GMC-registered doctor then reads every result and signs the report before it is released, so nothing reaches you unreviewed. There is no option to receive results without a doctor reading them first. The report arrives in your secure portal in plain English: each result with its unit and the laboratory's own reference range, and the doctor's note on what the set means read together. If a result sits outside its range the report says so and explains what usually happens next, which is most often a conversation with your own GP, who can act on it alongside your history and examination. Most reference ranges are set to cover about 95% of healthy people, so about 1 in 20 healthy people fall just outside any one of them. On a report with many results it is common for one to sit just outside its range, and a single number on its own rarely tells the whole story. If a result needs urgent attention, the reviewing doctor is alerted straight away and we contact you by phone the same working day rather than leaving it in the portal for you to find. If a specific result needs rechecking, the reviewing doctor says so in your report.
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