Looking to see if your vitamin B12 levels are normal? Keep in mind that B12 blood level tests don’t tell us nearly as much as people think they do. Here’s why:
- The low range of what’s considered normal B12 blood levels in most countries (100-250) is way too low, often missing desperately deficient folks. People show symptoms of B12 deficiency even in higher levels, as deficiencies begin to appear in the cerebrospinal fluid below 550. This is why Japan is treating anybody with levels lower than 500 with B12 injections. Those are levels that are considered normal in the US, and in most of the rest of the world. Where 200 is often accepted as a low normal not needing intervention, Japan and England have updated their low normal values to be around 500-550, and consider anything less to be dangerous.
- The serum vitamin 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 analogues 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 easily access these forms.
- The blood test doesn’t record what’s happening at the cellular level. Blood levels aren’t enough – we want to know what’s going on inside the cells, where it matters. Therefore, an assessment of B12 status by serum B12 levels is insufficient.
In short, you can’t rely on serum B12 levels to tell you the whole story. But you can use it as an indicator of some sort. Let’s give you an actual chart.
Normal Vitamin B12 Levels Chart
We often get questions such as, “My B12 is 201 (or 109, or 325, or 797 – you name it). Is that low? It is within my clinic’s vitamin B12 normal range chart!”. Well, normal values of vitamin B12 are considered, in most countries, to be between around 200 to 900 pg/ml. However, as mentioned, many people show symptoms within that range. Therefore, we would like to suggest Sally Pacholok’s recommended vitamin B12 range:
| B12 Status | B12 Levels (pg/ml) |
|---|---|
| Normal | 550 or higher |
| Deficiency | Less than 550 |
| For a healthy nervous system & disease prevention in the elderly | 1000 or more |
This B12 levels chart show the values suggested by Pacholok & Stuart in their book ‘Could it be B12?’. To quote, “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 tragedy is with people who are symptomatic but are in the low range of vitamin B12 normal levels, between 200-500. This is a grey zone, and even though these folks show clinical signs of B12 deficiency, they are never tested or treated because their B12 falls within the accepted B12 level range. This results in late diagnosis (if at all) and higher neurological injury incidence. So, don’t rely on a blood test alone.
How to Check For Healthy B12 Levels?
There are three ways to know if you have good B12 levels or not.
Methylmalonic acid (MMA)
B12 helps converting methylmalonyl CoA, one of the forms of MMA, into succinyl Coenzyme A. When you’re deficient in B12, MMA levels increase in both your blood and urine. You may be able to find MMA tests in private labs.
If you can’t find one, you can order a urinary MMA test from Dr. Eric Norman (founder of the test). The uMMA test is even better than the serum one, because B12 deficiency patients with neurological damage excrete significantly more uMMA than those without damage. Therefore, uMMA tests can predict one’s path toward permanent neurological impairments. The test has a whopping 99% accuracy, making it confirmatory.
Keep in mind, if you have kidney disease you may get false high levels with the serum MMA test, or false low levels with the uMMA test. That’s because the kidneys excrete the MMA in the urine. If they don’t function correctly, MMA may accumulate in your blood. Serum MMA levels may also be high in patients with thyroid disease or bacterial overgrowth in the small intestine. It may also be high in pregnant women or infants suffering from a rare genetic disease called methylmalonic acidemia.
However, if your uMMA levels are high, you probably have a B12 deficiency.
Holotranscobalamin (HoloTC)
Another useful test is the holotranscobalamin (HoloTC) test, which only records the active forms of B12 in the blood. Available at Viapath. This test should be a first-line diagnostic tool, and low levels may indicate B12 depletion at the cellular level.
We predict that this test will one day replace the current test, as there are often very large gaps between total B12 and active B12 in the blood.
Homocysteine
Another good way to assess one’s true B12 status is to measure total homocysteine (tHcy). Methyl B12 is needed as a co-factor to convert homocysteine back into methionine. If you have normal B12 values, but high homocysteine levels, this may point to a deficiency or problem utilizing methyl B12. High homocysteine levels can also be the result of low B6, folate, renal failure or hypothyroidism.
However, this test is a nice extra tool in the box.
By the way, we also recommend to test for folate (vitamin B9), ferritin (iron storage), and have a full blood count. This is because B12 and folate need each other, and optimal levels of iron are just as important as optimal B12 levels.
Rely On Symptoms
To quote NEQAS:
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.
The United Kingdom National Quality Assessment Scheme for Haematinic Assays
If you suspect you may have a B12 deficiency, take action immediately. Disregard blood vitamin B12 levels and go by symptoms alone. You can’t overdose on B12, and the risk is just too high. Wait too long, and permanent neurological damage may occur.
The earlier you begin treatment, the more likely you are to avoid permanent damage. Treating early, though, may reverse symptoms completely. There’s a time-limited window of opportunity for effective intervention, especially to those with cognitive dysfunction.
When you have a B12 deficiency, the myelin sheath around your nerves is being stripped off. If you have any symptoms, especially neurological, start injecting methyl B12 immediately. Do it for at least three months, because a red blood cell life-cycle is 90 days, so you want all the bad cells to expire and have new, healthy ones instead. Then, see how you’re feeling. Injections are the best way to rapidly replenish your stores.
Best of luck.
