Not just your B12 level — whether your cells can use it
Other Labs
Starting at $193
+ lab fees
TestWell
$79.99
A serum B12 test alone misses early and borderline deficiency — levels can look 'normal' while your cells are already running short. This panel adds the two functional markers clinicians use to settle the question: methylmalonic acid (MMA), which accumulates early and specifically when usable B12 is low, and homocysteine, which rises with both B12 and folate deficiency. Read together, the pattern is diagnostic: elevated MMA with elevated homocysteine points to true B12 deficiency, while elevated homocysteine with normal MMA points to folate instead. It's the right panel when B12 came back borderline, when deficiency symptoms (fatigue, numbness and tingling, brain fog, memory changes) persist despite a normal B12, or when you're verifying that supplementation is actually working. Note: MMA is a specialty assay, so results take longer than routine bloodwork.
Sample Type
Blood draw
Fasting
Required
Results In
5–12 business days
Biomarkers
3 across 3 tests
3 individual tests · 3 biomarkers measured — each test linked so you can learn more.
Fasting for 8–12 hours recommended (homocysteine reads most accurately fasted). Water is okay. MMA is a specialty send-out assay — allow extra time for results.
Fasting for 8–12 hours recommended (homocysteine reads most accurately fasted). Water is okay. MMA is a specialty send-out assay — allow extra time for results.
Starting at $193 at other labs
TestWell Price
$79.99
+ $6 lab processing fee at checkout
No insurance needed · HIPAA compliant
Individual tests that complement this panel
Comprehensive B12 Deficiency Panel
$79.99