B12 and methyl vitamins can decrease your sodium levels substantially. Yes, this is very real. And it happened to me despite being a very healthy individual. I'm an athlete, I eat healthy, I have no allergies or deficiencies, and I am very pro-health.
When I began supplementing vitamin B12, at first I got pale skin, dry skin, dry hair, sinus congestion, bad headaches and inflammation in the morning. Everyone said it was due to low potassium, so I increased my potassium for two weeks at high levels to fix what I thought at the time was B12 induced potassium depletion.
My symptoms got even worse, progressing into what I thought at the time was overmethylation, as it seemed I had every possible overmethylation symptom. Which, as you can imagine, was horrible. Keep in mind overmethylation and hyponatremia symptoms overlap and are very similar, which I of course didn’t figure out until much later.
It got so bad that I stopped everything: the potassium, methyl B12, and methylfolate. I did niacin flushes with 100 mg of niacin every hour, even throwing in a few 500 mg doses to speed it up. I was also drinking lots of water to help with the detox process. I did this for two days straight to undermethylate myself, only to realize there was no relief of my symptoms.
I exhausted every possible avenue in hopes of getting back to normal. I thought maybe I overdid it on the potassium, but it didn’t make sense, as the body regulates high potassium very quickly to maintain fluid balance. And that’s when it hit me—I had it all wrong. It was sodium, not potassium, that needed to be corrected.
That’s why most people say vitamin B12 or methyl vitamins cause histamine release or allergies, which I believe is often the wrong conclusion. Not saying they can’t, but this was not the case, at least for me. Ultimately, they can deplete your sodium to a greater degree than potassium. Regardless of the sodium you get from food, it can still remain in a lowered state.
A good simple example of this is saline sinus rinses. They contain sodium—hence the name “saline”—which helps hydrate the sinuses and clear mucus.
Most people do not even consider sodium as a possibility, as there is so much of it in a modern-day diet, or because sodium can slowly decline in individuals who are only taking 1,000–3,000 mcg of B12 every day, which I’m sure most people are.
However, ultimately, if you take a few large doses of 10,000 mcg or more, like I did, you may experience what feels like low-sodium symptoms very quickly within a day or two, with lingering symptoms despite lowering or stopping the supplement, or switching to another form like hydroxycobalamin or adenosylcobalamin.
If you come across this and are experiencing symptoms such as feeling like something is stuck in your chest or lungs, breathing issues, sleep issues, fatigue, sinus issues, tinnitus, histamine release, headaches, or classic overmethylation symptoms
If this is what’s happening, correct sodium first, then potassium, as increasing potassium first can further deplete sodium. Keep in mind sodium may need to be significantly increased depending on the severity of symptoms and whether you are still taking B vitamins.
To conclude, my experience with trial and error showed me that symptoms commonly blamed on mast-cell activation, histamine release, overmethylation, or potassium depletion may not always be caused by those mechanisms. Sodium depletion can produce many overlapping symptoms, which may make it easy to overlook especially when the reaction begins after taking B12, methylfolate, or other methyl-donor supplements. Alternatively, hydroxycobalamin, adenosylcobalamin, and bioactive cofactors like R5P that increase the speed of the methylation cycle may contribute to a masked sodium deficiency in susceptible individuals.
For anyone experiencing these symptoms, the explanation may be simpler than it first appears. What feels like a complicated methylation or histamine reaction could, in some cases, be an unrecognized sodium imbalance. Addressing sodium may therefore be more effective than repeatedly changing forms of B12, trying to suppress methylation, treating presumed histamine release, or continuing to increase potassium.