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How to flush B12 out of your system quickly? If that’s what you’re trying to do, you may be barking up the wrong tree. Most people (doctors included) fail to realize this:
If your blood test shows high B12 levels, it typically points to an underlying medical issue that releases B12 from the body’s stores into the bloodstream. In other words, high B12 levels in the blood are a symptom—not the cause—of a bigger problem. The elevated B12 should be a warning sign demanding an investigation.
Note: If you regularly take a B12 supplement, high levels are expected and don’t mean much. For this reason, doctors ask patients to stop supplementing two weeks before a blood test. In that case, there’s no need to worry about flushing B12 out of your system, as your body urinates excess over time.
Possible Underlying Conditions
The main conditions your doctor should try to exclude are certain blood disorders and cancers (which break down cells and release B12), liver diseases (which release stored B12), and kidney diseases (which prevent the body from flushing out excess B12).
See these studies:
The aetiological profile of high serum cobalamin predominantly encompasses severe disease entities for which early diagnosis is critical for prognosis. These entities are essentially comprised of solid neoplasms, haematological malignancies and liver and kidney diseases. This review reflects the potential importance of the vitamin B12 assay as an early diagnostic marker of these diseases.
The pathophysiology of elevated vitamin B12 in clinical practice
Elevated levels of serum cobalamin may be a sign of a serious, even life-threatening, disease. Hematologic disorders like chronic myelogenous leukemia, promyelocytic leukemia, polycythemia vera and also the hypereosinophilic syndrome can result in elevated levels of cobalamin. Not surprisingly, a rise of the cobalamin concentration in serum is one of the diagnostic criteria for the latter two diseases. The increase in circulating cobalamin levels is predominantly caused by enhanced production of haptocorrin. Several liver diseases like acute hepatitis, cirrhosis, hepatocellular carcinoma and metastatic liver disease can also be accompanied by an increase in circulating cobalamin. This phenomenon is predominantly caused by cobalamin release during hepatic cytolysis and/or decreased cobalamin clearance by the affected liver. Altogether it can be concluded that an observed elevation of cobalamin in blood merits the a full diagnostic work up to assess the presence of disease.
SIGNIFICANCE OF ELEVATED COBALAMIN (VITAMIN B12) LEVELS IN BLOOD
So, if your B12 levels are abnormally high (and you haven’t been supplementing), have the necessary tests done. Don’t wait—the sooner you’re evaluated, the better.
How to Lower B12 Levels Naturally
So, how can you reduce B12 levels? In the presence of an underlying illness, the best treatment for high B12 levels is to resolve the illness itself. Soon after you do that, B12 levels will return to normal. This should be your focus. The high B12 levels themselves are a minor issue—excess is harmless and there are no toxicity levels.
If you are concerned about decreasing your B12 levels, remember that B12 is a water-soluble vitamin. It dissolves in water, meaning the body absorbs only what it needs and can process, excreting the rest through urine. You can’t overdose. Consider this:
In cases of life-threatening cyanide poisoning, doctors inject 5,000,000 µg of B12, causing blood levels to skyrocket to 560,000,000 pmol/L. If needed, they will repeat the dose for a total of 10,000,000 µg—4.17 million times the recommended daily intake. Not only is B12 non-toxic at such massive doses, but it actually helps clear the cyanide from the body. Once the crisis is over, B12 levels eventually return to normal.
Just how long does it take for B12 to leave your system? Most excess is out within hours. However, if you supplement or if you suffer from an underlying condition, you will have excess B12 around the clock. Even so, there are no side effects at high levels.
Consider this study from Japan, where kidney dialysis patients with polyneuropathy received 5,000 µg of B12 three times a week for half a year. Because of poor renal clearance, the B12 remained in the blood, and levels rose from an average of 422 pmol/L to 54,000 pmol/L. Even at such huge levels, no side effects were recorded.
What is the treatment for high vitamin B12 if supplementing?
If you supplement with vitamin B12 regularly, such as with our methyl B12 injections on a daily basis, high levels in the blood are normal. Drink enough water, and your body will flush excess B12 out of your system through the urine gradually.
However, do not let high blood levels of B12 stop you from supplementing if you are treating a genuine B12 deficiency. We see it too often: doctors panic over these high levels and tell the patient to “stop for a while until levels drop.” There is nothing to worry about—send them to read this page. If you have a B12 deficiency, the risk of stopping treatment is far greater than the risk of having elevated B12 levels.
The Bottom Line
If you do not supplement and your blood test still shows high B12 levels, work with your doctor to find out what underlying condition is causing the elevated levels. Treat the root disease, and the B12 levels will naturally return to normal over time.
In short, focus on resolving the underlying issue rather than worrying about how to reduce B12 levels in blood. High B12 is simply a symptom of a larger problem.
All the best.