Vitamin B12 Test

About this test

Key Benefits

• Measures active vitamin B12 (holotranscobalamin) for more accurate results

• Helps identify B12 deficiency at an early stage

• Supports insights into energy levels, brain function, and nervous system health

• More sensitive marker than standard total B12 tests

• Simple at-home blood test, no clinic visit required

What This Test Measures

This test analyzes:

• Holotranscobalamin (Active B12): The bioavailable form of vitamin B12 that your body can use for cell function, DNA synthesis, and energy metabolism

Unlike total B12 tests, this marker reflects the amount of B12 that is actively available to your cells, making it a more reliable indicator of deficiency.

Who Should Take This Test?

This test is suitable for anyone who wants to assess their B12 levels, especially individuals experiencing fatigue, low energy, or neurological symptoms. It may be particularly relevant for vegans, vegetarians, older adults, or individuals with absorption issues or digestive conditions.

How It Works & Sample Collection

Order your kit online, collect a finger-prick blood sample at home, and send it back using the prepaid envelope. Your digital results are provided once the analysis is complete.

For best accuracy, take the test in the morning while fasting.

Analysis Method and Laboratory

Your sample is analyzed in an ISO-Certified laboratory using ELISA (Enzyme-Linked Immunosorbent Assay), ensuring accurate, reliable, and high-quality results.

Biomarkers included

• Holotranscobalamin (B12): Holotranscobalamin (holoTC) is the biologically active form of vitamin B12, representing the fraction of B12 that is bound to transcobalamin and available for cellular uptake. It is considered a more accurate and earlier indicator of functional vitamin B12 deficiency than total serum B12, as low levels directly reflect inadequate B12 delivery to tissues. This makes it crucial for assessing B12 sta

How to prepare

**1-2 weeks before:** Avoid high-dose B12 supplements unless you want them reflected in your results. **24-48 hours before:** No alcohol, smoking or excessive caffeine and excerise. **8-12 hours before:** Only drinking water to prevent interference from recent meals. **Medications:** Certain medications like proton pump inhibitors (PPIs), metformin, and some antibiotics can affect B12 levels.

Frequently asked questions

How does it work? / When do I get my results?

1. Order and receive your kit. 2. Perform the test. 3. Send a sample at the beginning of the week (to avoid delays). 4. Results digitally in 10–15 business days.

What is the difference between this test and a standard B12 test?

Standard B12 tests measure total B12, which includes both the active form and an inactive form that the body cannot use. Our test measures Holotranscobalamin, which is the biologically active form that actually delivers B12 to your cells. This provides a much more accurate picture of whether your body has enough usable B12.

Do I need to stop taking supplements before the test?

If you are taking B12 supplements or injections, it is recommended to wait at least 1-2 weeks after your last dose before testing to get an accurate representation of your baseline levels, unless your doctor has advised you to test while supplementing to monitor dosage efficacy.

Customer reviews

4.6/5 (5)

• 5/5 — Clear instructions and very easy to collect the sample at home.
• 4/5 — Good test, though the finger prick took a second try to get enough blood. Results were detailed and helpful for my diet.
• 4/5 — The lab turnaround was a bit slower than expected, but the data was high quality. Helpful for tracking my B12.
• 5/5 — Fast delivery and easy to use!
• 5/5 — Exactly what I needed to check my levels as a vegan.