Pernicious anemia is an autoimmune condition that prevents the body from absorbing vitamin B12, leading to megaloblastic anemia and potentially serious neurological complications. It is caused by autoantibodies that attack parietal cells in the stomach lining, destroying their ability to produce intrinsic factor, a protein essential for vitamin B12 absorption. The Intrinsic Factor Blocking Antibody test is the most important test for diagnosis because it directly confirms the autoimmune process.
90-day money-back guarantee
Lab order in minutes
Save a trip to the doctor
Low prices since 2005
Labs within 2 miles
Pernicious anemia is caused by an autoimmune reaction where your immune system mistakenly attacks parietal cells in your stomach lining. These parietal cells normally produce intrinsic factor, a protein that binds to vitamin B12 in your food and helps your small intestine absorb it. When the immune system destroys these cells, your body cannot produce enough intrinsic factor, which means vitamin B12 from your diet passes through your digestive system without being absorbed. Without adequate B12 absorption, your body cannot make enough healthy red blood cells, leading to anemia and potential nerve damage over time.
The Intrinsic Factor Blocking Antibody test is the most important test for pernicious anemia because it directly detects the autoantibodies that block intrinsic factor from binding to vitamin B12. A positive result confirms the autoimmune nature of the condition with high specificity. Additional supporting tests include the Parietal Cell Antibody test, which detects antibodies against the stomach cells themselves, and the Vitamin B12 test to measure actual B12 levels in your blood. The Methylmalonic Acid test is also valuable because it becomes elevated when your cells are not getting enough B12, even when serum B12 levels appear borderline normal. Together, these tests provide a comprehensive picture of both the autoimmune process and its effects on your vitamin B12 status.
You should get tested if you experience persistent fatigue that does not improve with rest, numbness or tingling in your hands and feet, difficulty walking or balance problems, pale or yellowish skin, or a sore, red tongue. Testing is also important if you have a family history of pernicious anemia or other autoimmune conditions, as there is a genetic component. If you are over 60 years old or have been diagnosed with another autoimmune disorder like thyroid disease or type 1 diabetes, you are at higher risk and should consider testing. Early diagnosis is critical because untreated pernicious anemia can lead to irreversible nerve damage, so do not wait if you notice these symptoms developing.
Save a trip to the doctor, go directly to the lab
Instant orders, results often overnight*
Results explained in simple language
Reviewed by US licensed doctors
Fast & confidential, we never sell or share your data
No insurance needed, transparent pricing
What this means
Your testosterone levels are slightly below the optimal range. While this is not necessarily cause for concern, it may contribute to occasional fatigue, reduced motivation, or lower muscle mass over time.
Recommended actions
Increase resistance or strength training
Prioritize 7–8 hours of quality sleep per night, try to reduce stress
Include more zinc- and magnesium-rich foods (like shellfish, beef, pumpkin seeds, spinach)
Consider retesting in 3–6 months
Not overhyped or overpriced. Just comprehensive blood testing made simple and for everyone.
505 reviews
Sample results
Your 24/7 Lab Guide
Quick questions:
