Question: Does it matter what form of B12 you take?

Cyanocobalamin is cheap and there's not really any clear evidence that it's harmful, but I just don't like the idea that it is cobalamin bound to cyanide. It's not found in the food supply. Forming cyanocobalamin and peeing it out is actually one of the main ways you detoxify cyanide.

Hydroxocobalamin is also relatively inexpensive. It's relatively easy to get as injections. It is not an end product of detoxification. It is found in very high concentrations in the food supply. The normal forms of vitamin B12 that you find in the diet from food are hydroxocobalamin and methylcobalamin in milk, and hydroxocobalamin and adenosylcobalamin in meat. Hydroxocobalamin is the most universal food form of cobalamin, and it is always a substantial part of the food supply. I'm pretty sure it's cheaper than methylcobalamin, so I would use intramuscular injections of hydroxocobalamin.

Most B vitamins start their absorption in the stomach and then mostly absorb in the small intestine. In the case of B12, when you're dealing with food, you're absorbing it in the small intestine almost exclusively with intrinsic factor that's produced in your stomach.

Start with a milligram of oral hydroxocobalamin. Test that against your serum B12. If it's not moving your serum B12, see if 2, 3, 4, 5, 6 milligrams do. Because if they do, then taking that every day is going to be probably easier. Well, I mean, it depends on what you like. But you're probably going to like taking oral B12 more than you're going to like getting intramuscular injections. I would see if raising the dose works first. I'd use oral hydroxocobalamin. Then if you have to use intramuscular, I will use hydroxocobalamin.

I guess you just have to judge it against from a medical perspective they're always worried about compliance, because unlike the people who are showing up to this AMA, the general population has very low motivation compared to us. Injection is preferable from that standpoint because there are fewer things to do. Plus, you have an accountability buddy because someone's got to inject you. You get an accountability buddy to do something once a month versus you have the personal responsibility to do something every day. From a compliance perspective, it's vastly superior, the getting injected. But if you're already taking 15 supplements every morning, then it's probably way easier for you to just add megadose of B12 in with those oral supplements than to get intramuscular injection. I'd prefer it.

This Q&A can also be found as part of a much longer episode, here: https://chrismasterjohnphd.com/podcast/2019/09/06/ask-anything-nutrition-march-8-2019

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S3 Ep19: The Six Nations Preview with Foxy & Geordan Murphy