Check out our Baseline test which includes this test PLUS 15 other markers for just £20 more

Vitamin B12

Check your active vitamin B12 levels with our home finger prick blood test kit analysed at one of our UKAS accredited UK labs.

This B12 blood test kit measures the active form of B12 which is the most accurate means of measuring your level of vitamin B12 (as opposed to total B12). Active B12 is the best early indicator of B12 deficiency.  

Vitamin B12 (along with folate) plays an essential role in the formation of red blood cells and also has a key role in nerve health. The human body doesn’t produce Vitamin B12, so it has to be absorbed through diet. Low levels of this essential vitamin can leave you feeling tired and weak while prolonged deficiency can lead to anaemia.

This test enables you to check your active B12 levels quickly and easily.  Simply send your sample direct to our lab and accurate results will be available within 48hrs on our secure online health dashboard. 

Special offer - Save £10
What's included in the price?
  • Finger prick or phlebotomy kit
  • Postage & packaging
  • Accredited lab analysis
  • Results within 2 days of receipt
  • Market leading results dashboard
  • Reviewed by a doctor or nurse

Why check Vitamin B12 ?

  • You want to check levels to ensure your diet is ok
  • You are suffering from low energy levels
  • You want to guard against anaemia
  • You want to check if you need to supplment or are over-supplementing

Benefits of vitamin B12 testing

By taking our home vitamin B12 blood test, you can get fast and accurate insights into your vitamin B12 levels.

If you’re experiencing a lack of energy or feelings of weakness, this test could identify whether a B12 deficiency is at the root of those issues.

By the same token, those who are simply being proactive about assessing their health and guarding against any future deficiency or anaemia will benefit from this accurate insight into existing levels.

Given that the body does not produce vitamin B12, our intake has to come from diet, a blood test to check your levels is an excellent indicator as to whether improvements might be needed to your diet in order to prevent a deficiency.

Our check includes a quick and simple finger prick test carried out at home. Your results will be made available in a simple, easy to read dashboard, where you can also track your levels over time and gain information, tips and advice on how to improve.

Biomarkers included in this package

Vitamins & minerals

Active B12

How it works

Collect sample

We will send you a finger prick kit to use at home

Post sample

Pop your sample in the post to us using a pre-paid envelope

Online results

View your results on your secure personal health dashboard

What our customers say

Efficient, great communication and information. Very fast, next day turnaround. Very, very pleased. Highly recommended and best value I have found.


Wasn’t feeling quite right and believed I may be chronically stressed. Took the baseline plus option which is a wider range of tests and this confirmed by expectations and also highlighted two further issues which I’ve raised with my GP. Well worth the piece of mind.


Fast easy service putting my mind at rest quickly. Sent off sample on Monday, got results back Tuesday afternoon.


The service was great from beginning to end. The test kit arrived quickly and was easy to use, the instructions were clear and simple to follow and my results were available sooner than I expected. Thanks everyone!


As a working mum, I often find myself training ‘tired’ as the demands of day-to-day life take their toll.  Forth has enabled me to gain a valuable insight into what is happening ‘under the surface’, so I  can adapt my training and lifestyle.

Kate Allan

Really fast and reliable results.So easy to use! Have used them3 times now and will continueto use this company, amazing.


I'd put off getting regular blood tests before because of the long-winded process of a GP visit. Forth has changed all that. The process is very quick and very easy, with thorough, well-explained results delivered to your inbox within days.

Alice Hector

I enlisted the help of Forth to help me get to the bottom of my current health concerns. The test was really easy to and my results were available within day. Using Forth has helped me take the action needed to get my hormones back on track.

Holly Rush, 39

Really excellent service - we bought two 'vitality' tests after reading about Forth With Life in Natural Health magazine. The packs came quickly, the phlebotomy appointment at home was convenient and professional and the results were quick and insightful- I recommend without reservation to anyone wishing to gain a comprehensive understanding of biomarkers indicative of their health and wellness!

Kate W

I suffer from a hereditary condition which causes my body to store too much iron.  My biggest issue before using Forth was getting an appointment with my GP.  Now using Forth I can track my iron quickly and easily and take action before levels start to affect my health

Mark Threfall, 29

Forthwithlife are just so helpful - professional and extremely easy to deal with. I would highly recommend these guys and would literally never look anywhere Else. Superb company.


Taking the test is simple just make sure you follow all the instructions so you follow the correct procedures. The customer service is second to none and the results are easy to understand and follow.

Matthew Bottrill

As a former Olympic cyclist I always wanted to look after my health. This has never changed to this day but become a lot easier via Forth, it’s the only way to really understand your own body. 

Brian Smith

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