Vitamin B12 is great. It helps form red blood cells. It is crucial to the synthesis and repair of DNA and the myelin sheath, a layer safeguarding our nerves. It also aids optimizing our homocysteine levels, decreasing our risk of blood clotting and heart attack. But can we actually have too much B12?
That’s what this post is about.
Can too much vitamin B12 hurt you? Can it not? Is vitamin B12 toxicity a scary possibility, or can we just continue injecting ourselves with huge doses with no mercy? Here’s everything you need to know about vitamin B12 overdose.
Vitamin B12 Overdose Symptoms & Side Effects
Can you take too much B12?
Short answer: No.
Certain vitamins can harm you when taken in excess, specifically fat-soluble vitamins like A and K which will build up in your fat stores. Vitamin B12, however, is water soluble and will be flushed out in your urine if taken in excess. Therefore, there are no vitamin B12 overdose symptoms.
The recommended daily dose is very low, about 2-3µg, yet many supplements deliver hundreds or thousands of µg per dose. This is no mistake. There’s a reason no upper limit for B12 has been set by The Food and Nutrition Board.
B12 (the methylcobalamin form) has been used in ultra-high doses (25 to 50 thousands of µg doses!) to prolong survival of ALS patients and aid patients with peripheral neuropathy and chronic axonal degeneration. It is also used in huge amounts to detoxify cyanide poisonings.
We’re talking here about 25,000 or 50,000µg doses. That’s more than 10,000 times higher than the recommended daily limit, yet it still causes no excess vitamin B12 toxicity symptoms.
Summary: Can You Have Too Much B12?
Can you overdose on B12?
No matter if you inject yourself or consume a ton of vitamin B12 foods every day, any vitamin B12 excess will be excreted in your urine. My point?
This article is part of a larger guide: Vitamin B12.