Is your cobalamin (B12) high, but everything else seems normal?
In our article about high B12 levels, we discuss how elevated levels of B12 are not dangerous by themselves, but may actually indicate an underlying illness:
Elevated levels of serum cobalamin may be a sign of a serious, even life-threatening, disease. Hematologic disorders like chronic myelogeneous leukemia, promyelocytic leukemia, polycythemia vera and also hypereosinophilic syndrome can result in elevated levels of cobalamin … Several liver diseases like acute hepatitis, cirrhosis, hepatocellular carcinoma and metastatic liver disease can also be accompanied by an increase in circulating cobalamin.SIGNIFICANCE OF ELEVATED COBALAMIN (VITAMIN B12) LEVELS IN BLOOD
As noted, both cancer and liver disease are examples. In cancer, cell destruction could release B12 into the blood, elevating B12 levels. However, in these conditions you’re likely to see other signs and abnormal blood markers as well, not just high B12.
But, what if you show high B12 levels, yet everything else is normal?
High B12, Everything Else Normal
We address three key questions:
- How high are your B12 levels?
- How normal is everything else?
- Do you supplement with B12 regularly?
How High Are Your B12 Levels?
In most places, the cutoff for B12 deficiency is way too low. People show deficiencies even around the 400-500 pg/mL range. This happens because the common test measures all of the B12 circulating in the blood, of which the majority is inactive and non-available. As a result, many people believe their B12 levels are good, while they actually have a B12 deficiency. In such cases, an active-B12 test would have revealed the deficiency, which is why we hope one day this test will become the default.
Conversely, the suggested upper-range levels are also lower than they could be. If your test comes back with levels of say, 1,200 pg/mL, it will likely be marked in red.
Mount Sinai Hospital in New York, for instance, recommends levels of 160 to 950 pg/mL. Again, 160 is way too low, and levels above 950 aren’t automatically concerning. In fact, in Could It Be B12?, Sally M. Pacholok advises to keep levels near or above 1,000 for a healthy nerve system and disease prevention in the elderly:
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.
Our point is that many healthcare facilities will warn you of having high levels of B12, when there’s likely nothing to worry about. There are no toxicity levels to B12, and the recommended range is far from optimal to begin with. Keep that in mind.
How Normal Is Everything Else?
If your B12 levels are high, then our next question would be: is everything else truly normal? We’re not simply talking about blood markers, but about the overall clinical picture. To quote the UK NEQAS for Haematinic Assays:
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.
Of course, the reference is to B12 deficiency. Here again, the opposite is also true. If your B12 levels are higher than usual but no other sign exists, there’s likely no issue. However, if you do show symptoms and if you’re not feeling well – even if all other blood markers seem fine – act quickly and do the necessary tests. Prompt diagnosis is crucial.
Do You Supplement With B12 Regularly?
If you supplement with B12 on a regular basis, high levels in the blood are absolutely normal, even expected. If you supplement daily, you’re going to have high levels around the clock. Don’t worry – B12 is harmless. Drink enough water, and any excess of B12 will flush out of your system through the urine. You can’t overdose on B12.
When a B12 blood test shows 1,000pg/ml, around 5μg floats in the blood. After a good steak, levels can elevate to more than 1,500pg/ml for a short duration. If you inject our 1,200μg B12 shots on a daily basis, your blood could see levels of 250,000pg/ml (!) for a few minutes after a shot, if the machine is capable of identifying such amounts.
Most excess is flushed through the urine rapidly, while the body uses the rest, or stores it in the liver, kidneys and muscle tissue for future use.
Again, nothing to worry about, as B12 is non-toxic. When people suffer a severe cyanide toxicity, medics inject them with 5 million µg of B12. Blood levels soar to hundreds of millions of pmol/L, and sometimes they repeat the injection, totalling 10 million µg. This is 4 million times higher than the recommended daily dose, yet it is still harmless. In this case, the B12 counteracts toxicity, since it clears the body of the cyanide.
So, if your blood test shows high B12 levels, but everything else seems normal, you should keep a couple of things in mind:
- The standard B12 range of 160 to 950 pg/mL is far from optimal. We actually encourage people to maintain levels of around 1,000 pg/mL.
- The clinical picture says a lot. If you feel great and the other blood markers are fine, maybe there really is nothing to worry about.
- If you’re supplementing with B12 regularly, expect very high levels.
If, however, you do not supplement and still show elevated B12 levels – with likely other symptoms too – then do the necessary tests to see what underlying disease is causing the high levels. For example, liver and kidney diseases are known to cause high levels. Treat the disease, and you’ll naturally get the B12 levels in order.