Update: Need injections? check this out.
Looking to know whether you have normal B12 levels or not? First know that B12 blood level tests don’t tell us nearly as much as you think they do:
- “Normal” B12 blood level ranges in most nations (~200-900, sometimes 100-900!) are way too low, often missing desperately deficient folks. People show symptoms of B12 deficiency within those ranges, as deficiencies begin to appear in the cerebrospinal fluid below 550. That’s why Japan set their lower limit to 500, treating people with B12 injections even when their blood levels are considered normal in the U.S. or U.K.
- The serum B12 blood test isn’t reliable; it measures the total amount of B12 in the blood, not distinguishing between active and inactive forms of B12. Inactive analogies of B12 (transcobalamin I and III) may represent as much as 80% of your blood levels. If a significant amount of your B12 is inactive, a test may show that you have normal B12 levels. Your body can’t access any of those inactive forms.
- The blood test doesn’t record what’s happening on the cellular level. Therefore, assessment of B12 status by serum B12 levels is insufficient.
Normal B12 Levels Chart
Normal values of vitamin B12 in blood are considered, in most countries, to be between 200 to 900 picograms per milileter. However, as I said, many people show symptoms even within that range. Therefore, I would like to suggest the following vitamin B12 normal range pg/ml:
|B12 Status||B12 Level|
|Adequate to maintain a healthy nervous system and to prevent disease in elderly individuals||1000pg/ml|
Note: This vitamin B12 levels chart contain the values suggested by Pacholok & Stuart in their book ‘Could it be B12?’: “At this time, we believe normal serum B12 levels should be greater than 550 pg/ml. For brain and nervous system health and prevention of disease in older adults, serum B12 levels should be maintained near or above 1000 pg/ml.”
The Danger of “Grey-Zone” Normal B12 Levels
The greatest danger that I see is for people who are symptomatic and have serum B12 levels in the lower normal range. normally 200-500. Those folks show clinical signs of B12 deficiency but are never further tested or treated because their B12 levels fall within the grey-zone.
This results in delayed diagnosis (if at all) and a higher neurological injury incidence. So don’t rely on a blood test alone! The United Kingdom National Quality Assessment Scheme for Haematinic Assays (NEQAS) warns:
In the event of any discordance between clinical findings of B12 deficiency and a normal B12 laboratory result, then treatment should not be delayed. Clinical findings might include possible pernicious anaemia or neuropathy including subacute combined degeneration of the cord. We recommend storing serum for further analysis including MMA, or holotranscobalamin and intrinsic factor antibody analysis, and treating the patient immediately with parenteral B12 treatment.
How to Really Test for Deficiency?
So, how do you actually test for B12 deficiency? As I said, the amount of B12 flowing in the blood isn’t a great indicator. Here’s a more conclusive one:
Methylmalonic acid (MMA) test.
One of what B12 does is it aids the conversion of methylmalonyl CoA, one of the forms of MMA, to succinyl Coenzyme A. When you’re deficient in B12, MMA levels increase in both your blood and urine.
You should be able to order a test, especially as a follow-up to a blood test showing low levels of B12, or levels in the lower end of the normal range. MMA test is a lot more indicative than a normal B12 blood test, with a whopping 99% accuracy with urinary MMA tests, making them confirmatory.
Serum MMA tests are widely available in private labs. If you can’t order an MMA test from your clinic, there’s a private urinary MMA (uMMA) test available from Dr. Eric Norman (founder of test), which is even better than the serum test. This is because B12 deficient folks with neurological damage excrete significantly more uMMA than those without. uMMA tests, therefore, can predict one’s path toward permanent neurological impairments.
One thing though. If you have kidney disease, you may get falsely high levels with the serum MMA test, or falsely low levels with the urinary MMA test. This is because the kidneys help excrete the MMA in the urine. If they don’t operate correctly, MMA may accumulate in your blood instead of being flushed out. However, if your uMMA levels are high, you’re probably B12 deficient.
Serum MMA levels may also be increased in people thyroid disease, bacterial overgrowth in the small intensity, and pregnant women. Also in infants suffering from a rare genetic disease called methylmalonic acidemia.
I recommend asking your doctor to test for folate (vitamin B9), ferritin (iron storage), and do a full blood count. This is because B12 and folate need each other, and a healthy level of iron is just as important.
Another good test is Holotranscobalamin (HoloTC), a test that only records active B12. I believe it can only be done privately. Available at Viapath.
Not Sure If You Have Normal B12 Levels or Not?
If you suspect you may be B12 deficient, take action immediately. Disregard the blood numbers and go by symptoms alone. That is because you can’t overdose on B12, and the potential damage is too high to risk. If you wait too long, permanent neurological damage may occur. Again, the earlier you begin treatment, the more likely you’ll avoid permanent damage.
Treating early often reverses symptoms. But wait too long, and you run the risk of having irreversible nerve injuries. According to this study, “there may be a time-limited window of opportunity for effective intervention in patients with cognitive dysfunction and low serum cobalamin (B12).“
Remember: When you have B12 deficiency, the myelin sheath protecting your nerves is being stripped off. If you sense any symptoms, especially neurological, start supplementing immediately, for at least three months (a red blood cell lifecycle is 90 days), and see if you feel (often much) better.
Regardless of why you’re B12 deficient, methylcobalamin B12 shots are always the quickest way to replenish your stores. This is because injected B12 skips gastric metabolism and is being carried directly to your blood.
High B12 Levels?
If your test shows elevated B12 levels (thousands pg/ml or more, sometimes a lot more), in the absence of supplementation, this is a sign of liver disease or cell death and the breakdown of tissues, releasing B12 back into circulation. In those cases, check yourself for liver disease and cancer.
However, if you’ve been supplementing for a while, high vitamin B12 levels are normal. Most of it gets flushed out in your urine; the rest is being absorbed in the liver, kidneys and muscle tissues.
Did you know? If you have 1000pg/ml, only about 5mcg floats around in your blood. Have a good B12-rich steak dinner and your serum level shoots up to more than 1500pg/ml for a short duration. With my recommended methyl B12 injections, if you did a blood test right after a 1,200mcg shot was absorbed, you’d get a recorded level of ~250,000pg/ml for a few minutes! Inject two or three times a day and you’ll have a similar high blood level around the clock.