Intrinsic Factor Abs, Serum
This test detects antibodies that block intrinsic factor, a protein needed to absorb vitamin B12 in the stomach. It's ordered when B12 levels are low or symptoms of deficiency (fatigue, numbness, cognitive changes) appear, helping distinguish autoimmune pernicious anemia from other causes of B12 deficiency.
When elevated: An elevated level indicates autoimmune attack on intrinsic factor and is the hallmark of pernicious anemia. This leads to vitamin B12 deficiency, which can cause anemia, nerve damage, and fatigue if untreated. When low: A low or negative result makes autoimmune pernicious anemia unlikely. However, B12 deficiency can still occur from other causes such as dietary insufficiency, stomach surgery, or other absorption problems.
Not especially athlete-specific. However, B12 is essential for energy metabolism and red blood cell formation; deficiency impairs aerobic capacity and recovery. Endurance athletes, vegans, and those with GI issues should monitor B12 status, but this antibody test is primarily a diagnostic tool for autoimmune causes rather than a performance or training marker.
Turnaround Time
2 days (up to 4 days)
Order online
Choose your lab and check out. We send your lab requisition automatically — no doctor visit needed.
Get your sample collected
Visit a lab service center near you for a quick blood draw (or book at-home phlebotomy where available).
See your results
Your results land in your Insider portal, ready to review and act on — that easy.
Your price
$12.50$40
3.2× less than retail
Versus the typical direct-to-consumer retail price for this test (illustrative — consumer prices vary by provider and region).
$12.50
Intrinsic Factor Abs, Serum
This test detects antibodies that block intrinsic factor, a protein needed to absorb vitamin B12 in the stomach. It's ordered when B12 levels are low or symptoms of deficiency (fatigue, numbness, cognitive changes) appear, helping distinguish autoimmune pernicious anemia from other causes of B12 deficiency.
When elevated: An elevated level indicates autoimmune attack on intrinsic factor and is the hallmark of pernicious anemia. This leads to vitamin B12 deficiency, which can cause anemia, nerve damage, and fatigue if untreated. When low: A low or negative result makes autoimmune pernicious anemia unlikely.
The Intrinsic Factor Blocking Antibodies test starts at $12.50 at Labcorp. No doctor's visit and no insurance needed; we do not bill insurance. Fitomics Insider members pay from $8.35.
Results for the Intrinsic Factor Blocking Antibodies test are typically ready about 2 days after your draw, and up to 4 days for some samples. Your results land in your Insider portal.
No. When you order the Intrinsic Factor Blocking Antibodies test from Fitomics Research Labs, a licensed physician in our 50-state network reviews and signs your requisition after checkout, and it lands in your portal and inbox. Then visit any Labcorp, Quest, or BioReference patient service center for your draw; results post to your Insider portal.
Looking for something else? Browse every test by category.
