The dose he uses
Someone asked him this on the episode, straight out, and he answered it just as plainly.
Dr. Martin, The Doctor Is In, Episode 1530Okay, well, I like about 4,000 micrograms a day of B12.
That is a big number next to what most multivitamins carry, and it is deliberate. His view is that B12 is hard to take up in the first place.
Dr. Martin, The Doctor Is In, Episode 1530It's finicky. What does that mean? It's hard to absorb on the best of days and combine that with the fact that people don't eat red meat like they used to.
The blood number he wants
The dose only makes sense against a target, and he has one.
Dr. Martin, The Doctor Is In, Episode 1530The best numbers for B12 are between 800 and 1200 for B12.
So the honest answer to how much you need is however much gets you into that band and keeps you there. For a woman over 60 who eats red meat regularly, that may be less than she thinks. For a woman who does not, he is blunt.
Dr. Martin, The Doctor Is In, Episode 1530Guys, if you're not eating red meat, I guarantee you your B12 is low.
Why normal on a lab is not optimal
This is where most women stop asking, because the report said normal.
Dr. Martin, The Doctor Is In, Episode 1530Because the blood tests that you get for B12 are highly inaccurate.
He walks up the range out loud on this episode. Two hundreds, three hundreds, four, five, six, even the seven hundreds, and calls all of it too low for you. None of that gets flagged. The study he was reading tied low normal B12 to cognitive decline, which is why he keeps pushing the number up rather than settling for unflagged.
The background on why so many people sit down there is here: why are people so low in B12.
"You want to be optimized, okay?"
Dr. Martin, The Doctor Is In, Episode 1530The form that raises it
Dose is half the answer. The other half is how it goes in.
Dr. Martin, The Doctor Is In, Episode 1530When you take an oral sublingual under the tongue, let it melt sublingual B12 methylcobalamin and you do it daily, that's the best way to elevate your B12 levels.
He is not guessing at that. He says he measured it in clinic, and that people taking it daily came up faster than people getting shots. He has nothing against the shot and gave plenty of them. The daily one simply wins on frequency. More on that here: sublingual B12 vs the B12 shot.
Two words on the label matter. Sublingual, so it melts under the tongue instead of going through a stomach that may not have the acid to release it. And methylcobalamin, which is the form he names.
When he goes higher
Dr. Martin, The Doctor Is In, Episode 1530If you're low, really low, you can take 8,000 micrograms of B12 a day.
Really low is the condition, not a starting point. And there is a whole group he expects to sit down there.
Dr. Martin, The Doctor Is In, Episode 1530If you're on any medication I can almost guarantee you you're going to be low in B12, okay?
He names diabetic medication like metformin, blood pressure medication and the acid reducers for reflux. He also adds one most people never connect to a vitamin.
Dr. Martin, The Doctor Is In, Episode 1530High cortisol, by the way, knocks B12 right out of your body.
And the plain fact of getting older, which he applies to himself.
Dr. Martin, The Doctor Is In, Episode 1530I'm older. We don't absorb properly, okay? It's just the way it is.
Nothing here is a reason to start or stop anything a doctor has prescribed. Talk to your doctor first.
Can you take too much B12
He tells a story about a physician who rang him worried about a patient's high B12 result.
Dr. Martin, The Doctor Is In, Episode 1530Well, it's a water soluble. Nothing happens if your B12 is high.
Nobody is in an emergency department because of a high B12, is his point. He still wants the same band, 800 to 1200, as the thing you aim at.
The clues he watched for
These are the patterns he says he saw in clinic when he measured B12. They are not a diagnosis, and plenty have other causes.
- Any digestive trouble at all, bloating or acid reflux, because it blocks absorption
- Not eating red meat
- Being on medication, particularly metformin, blood pressure pills or acid reducers
- Migraines
- Ridges in the fingernails
- A funny feeling in the tongue, mouth or lips
- Numbness and tingling in the fingers or feet
- Muscle weakness, because nerves feed muscles
- Tired but not sleeping properly
- Memory not quite sharp, since he calls B12 a brain and nerve vitamin
- Anemia, because B12 is part of making red blood cells
His advice at your next blood draw is to insist B12 is on the requisition. If you do not ask, he says, a lot of the time you do not get.
Common questions
How much B12 does a woman over 60 need a day?
Dr. Martin uses about 4,000 micrograms a day, as a sublingual taken daily, and goes to 8,000 micrograms for someone who is really low. He judges it against a blood level of 800 to 1200.
What B12 level should I aim for?
Between 800 and 1200. He walks up through the two hundreds to the seven hundreds and calls all of it too low, even though none of it gets flagged on a report.
Is sublingual B12 better than a shot?
He says yes, on frequency. A daily sublingual methylcobalamin raised levels faster in his own measurements than shots did, and he is not against shots.
Can you take too much B12?
He says nothing happens when B12 reads high, because it is water soluble. He still wants people landing in the 800 to 1200 band.
Read next: What Supplements Should A 65 Year Old Woman Take? and Should A Woman Over 60 Take Creatine?.
Get the dose right
Martin Clinic's Vitamin B12 is a sublingual methylcobalamin, 4000 mcg in one daily serving, which is the number he names.
60-day money-back guarantee.These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Always consult your healthcare practitioner before starting a new supplement, especially if you are pregnant, nursing, taking medication, or have a medical condition.
