Tweet	Vegan For Life by Jack Norris, RD & Ginny Messina, MPH, RD
For Updates: Follow @JackNorrisRD or subscribe to JackNorrisRD.com

Alternatives to Cyanocobalamin: Methylcobalamin & Dibencozide

Contents

• Introduction
• Methylcobalamin in a Small Sample of Vegans
• Therapeutic Use of Coenzyme Forms of B12
• Hydroxocobalamin
• Vegan Sources of Methylcobalamin
• References

Introduction

The typical non-cyanocobalamin forms of vitamin B12 in supplemental forms are methylcobalamin and adenosylcobalamin (also known as 5'-deoxyadenosylcobalamin, dibencozide, coenzyme B12, cobamamide, and cobinamide). Calling adenosylcobalamin "co-enzyme B12" is somewhat misleading because methylcobalamin is also a co-enzyme form of B12. Hydroxocobalamin is the form typically used in B12 injections.

Some researchers question whether these non-cyanocobalamin supplements are stable in their oral form. For this reason, much larger amounts are typically used with the hope that at least some is absorbed intact. One study suggests that once absorbed, methylcobalamin may be retained in the body better than cyanocobalamin (1).

We received the following anecdotal report (2011):

I'd been taking 500 mcg of methylcobalamin for years, not knowing that the B12 dosages so often cited (daily 25 - 100 mcg) are just for cyanocobalamin. So, about a week ago I started taking 1000-2000 mcg of methylcobalamin instead of just 500 mcg, and I feel a difference!

Methylcobalamin in a Small Sample of Vegans

Donaldson (2) (2000, USA) studied 3 vegans with elevated uMMA levels who were treated with 1/2 to 1 sublingual methylcobalamin tablet, 2 times/day for 3 weeks. Correspondence with the author (March 21, 2002) verified that these tablets contain 1,000 µg methylcobalamin each.

Two of the subjects' urinary MMA normalized while the remaining subject's stayed slightly elevated at 4.1 µg/mg creatinine (normal is < 4.0 µg/mg creatinine). Thus, at a rate of 1-2,000 µg/day, methylcobalamin appears to be absorbed at a high enough rate to improve B12 status in some vegans. Additionally, this indicates that the methylcobalamin was able to improve the MMA pathway which requires adenosylcobalamin (in other words, methylcobalamin was apparently converted into adenosylcobalamin in these people).

Therapeutic Use of Coenzyme Forms of B12

The coenzyme forms of B12 appear to be more effective in treating certain conditions than is cyanocobalamin (though they are often injected rather than taken orally). Kelly (3) (1997) reviewed the research on supplementing with the coenzyme forms of B12 (methylcobalamin and adenosylcobalamin). Results of studies performed on humans are listed here:

Table 1. Conditions Reported to Improve by Coenzyme Forms of B12
	Therapeutic dose recommended by Kelly3	Conditions reported to improve from treatment3,A
Methylcobalamin	1500-6000 µg/day	Diabetic neuropathy Infertility Hyperhomocysteinemia in diabetes Sleep disordersB Bell's Palsy
Adenosylcobalamin, aka: 5'-deoxyadenosylcobalamin, dibencozide, coenzyme B12, cobamamide, and cobinamide	1000-6000 µg/day	Neurological problems secondary to anorexia Hepatitis A Viral hepatitisB
A - In many cases, treatment was not compared to cyanocobalamin B - More effective than cyanocobalamin

Hydroxocobalamin

Hydroxocobalamin is the form of B12 typically found in food. There are not many oral forms for people to take; it is normally injected. One study suggests that after injections, hydroxocobalamin is retained in the body better than cyanocobalamin (4).

Vegan Sources of Methylcobalamin

• Enzymatic Therapy
• Wonder Laboratories Please note that their statement "The liver does not convert the cyanocobalamin form of vitamin B-12 into adequate amounts of methylcobalamin," implies that all vegans need a source of methylcobalamin. In fact, most vegans can rely solely on cyanocobalamin. Their Supplement Facts label (to show it is vegan) is below:
  

---

References