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Vitamin B12: Types, Brands, Dosage Levels, and Methods

If We Don't Eat Animal Flesh Twice a Day, We Might Need a Top-Quality Active-B12 Supplement

by Jon Sasmor

Last Updated July 8, 2018

Background: A Story About Poop

Once upon a time, people and animals pooped freely all over the land where they found their food. People used manure for fertilizer too. The soil was rich with germs. And rich with the mineral cobalt too.

Bacteria in the human large intestine and in poop made the mineral cobalt into vitamin B12 ("cobalt vitamin," "cobalamin"). The B12-making bacteria and the vitamin B12 they made were spread all through the soil and into and onto the plants.

People couldn't make their own B12. The bacteria that make it are in the large intestine, but absorption is upstream in the small intestine. So people and other animals ate the B12-containing plant foods. If people ate other animals, they got B12 from the animal too. Every meal had a tiny but significant amount of B12, since B12 was more or less everywhere, in very small amounts. (See Matesz 2011.)

Consistent with what was available, people were made to absorb a tiny amount, 1.5 mcg, with every meal, and to store some extra B12 in the liver for times of famine. B12 deficiency was so unexpected that the body's cells would mistakenly identify B12 deficiency as methionine deficiency, in a phenomenon called the methyl trap hypothesis (Scott 1981).

Then things changed. We discovered sanitation, which helped a lot in making people live longer with less infectious disease. Farming became mechanized and sterilized for improved efficiency and less infectious disease. The poop and bacteria were no longer going into the soil where the plant foods grow. And cobalt became depleted from the soil. Plant foods no longer had reliable B12.

Now, for many reasons, many people are reducing their reliance on animal foods and eating more of the healthy plant foods. But are they getting enough B12?

In our natural habitat, 2 or 3 of any plant or animal meal in a day would give us enough B12. Now, aside from supplements and fortified foods, it really would have to be 2 or 3 meals containing at least a small amount of animal flesh. Eggs and milk have a little bit of B12 and might help get enough, but the amount is marginal.

Could sterilized, depleted soils without B12 and slow-developing widespread B12 deficiency problems be a contributing reason for many of the developing modern diseases?

Vegans Need B12

Vegans need B12. Vegans, please don't let vegans go without B12! Many vegans are B12 deficient, as many as 80%. Vegetarians too. (Woo 2014; Obersby 2013; Herrmann 2003.)

Eating a diet of modern plants risks B12 deficiency. Those few exceptional vegans who seem healthy long-term even without a B12 supplement might have these similarities:

  1. were on a totally or mostly raw food diet
  2. grew a proportion of their food themselves
  3. lived in a very health conscious manner, and had a history of detoxing and fasting
  4. led a spiritual life, practiced yoga, meditation and similar activities likely to contribute to low stress levels"

(Rotter 2016.)

B12 deficiency symptoms can be subtle or unnoticed, and may develop over the course of years (Obersby 2013). B12 affects so many body processes that the list of B12 deficiency symptoms is long and non-specific.

Vegans with gradually worsening health suffer the effects of too little B12. And they give fuel to widespread criticisms and prejudices against vegans, against vegetarians, and against omnivores who reduce their meat-eating.

The best test for B12 status might be whether you respond positively to a top-quality B12 supplement. Those who need B12 will feel benefits when taking B12. Keep reading to learn more!

Biochemical Forms of Vitamin B12

Many of the common suggestions about B12 will leave some people B12 deficient anyway. This includes use of the common synthetic form cyanocobalamin found in "vitamin B12" supplements, fortified plant foods, and nutritional yeast. (Obersby 2015; Obersby 2013; Kelly 1997.)

The 1964 Nobel Chemistry Prize winning research on vitamin B12's structure mistakenly concluded that a cyanide group (—CN) was an intrinsic part of vitamin B12 (Hodgkin 1958). Since then, almost all research on vitamin B12 has been done on cyanocobalamin, with mixed results (for example: Greibe 2017; Brasky 2017; Arendt 2016; Ebbing 2009; Zhang 2008).

However, B12 science is still under development. The active-form methyl B12 recently was shown effective to normalize homocysteine levels in B12-deficient vegans and vegetarians (Obersby 2015).

Cyano B12 doesn't naturally occur in soil, poop, or even in animal foods. Instead, methyl B12, adenosyl B12, and hydroxy B12 are the primary forms of B12 in fertile soils, in animal foods, and in our metabolism.

People most sensitive to the effects of vitamin B12 respond best to the body's active co-enzyme forms, methyl B12 and adenosyl B12 (Freddd 2013). That's why the supplement brands suggested in the next section all are methyl B12 or adenosyl B12.

Form of B12 Nicknames Function in Body
Methylcobalamin Methyl B12, MeCbl

Recycles methionine in the methylation cycle, allowing hundreds of critical chemical reactions

Recycles folate in the folate cycle, allowing DNA production for new cells

Adenosylcobalamin Adenosyl B12, AdoCbl, Dibencozide, Cobamamide

Metabolism of certain fatty acids and amino acids

Healthy myelination of nerves

Hydroxocobalamin Hydroxo B12, HyCbl

Combines with glutathione to make the storage form of B12

May block methyl B12 and/or adenosyl B12 function for some people

Cyanocobalamin Cyano B12, CyCbl

No known function

Byproduct of detoxifying cyanide, rapidly excreted

Effectively converted to methyl B12 and adenosyl B12 by some people

May block methyl B12 and/or adenosyl B12 function for many people

Related Article: Vegans and Methylation.

Brands of Vitamin B12 Supplements

Those sensitive to the effects of B12 can notice huge differences in the potency of various brands. The brand may matter more than the nominal dosage amount on the label. For example, I personally have found Enzymatic Therapy methyl B12 three times as effective as the Solgar brand, despite both being labeled as 1000 mcg methylcobalamin tablets. The recommended brands from highly B12-responsive individuals on the Phoenix Rising forums who have tested many brands include:

  • Enzymatic Therapy B12 Infusion (Methyl B12)
  • Anabol Naturals Dibencozide (Adenosyl B12)
  • B12 Oils Adenosyl Methyl Oil (both Adenosyl and Methyl B12).

(Freddd 2013, 2014a, 2014b, 2014c, 2015; Garyfritz 2014.)

I receive no financial benefit from promoting any of these brands. I usually end up giving B12 Infusion to family and friends.

The number of available methylcobalamin products has skyrocketed the last few years. There might be other good brands, but I don't know about them yet. To my knowledge, Enzymatic Therapy B12 Infusion might the gold standard against which to compare other brands of methylcobalamin sublinguals.

These dosages should be plenty for most people:

  • Moderate dosage. ~250 mcg methyl B12 daily. Get a cutting board and sharp knife. Cut an Enzymatic Therapy B12 Infusion (methyl B12 1,000 mcg) tablet into as many parts as possible. That might be 10 or 12 parts; any smaller and the bits will crumble. Two or three times a day, put one of these small bits between your upper lip and gum to dissolve slowly. Approximate cost: $0.05 USD per day.
  • Strong dosage. ~250 mcg methyl B12 + ~500 mcg adenosyl B12 daily. Do the same as for Moderate dosage. In addition, cut an Anabol Naturals Dibencozide (adenosyl B12 10,000 mcg) tablet into as small bits as possible. That might be around 15 or 20 tiny bits. In addition to the methyl B12 two or three times a day, separately take an adenosyl B12 bit under the upper lip, once a day, or once every other day. Try taking the methyl and adenosyl B12s at separate times for enhanced effect. Experiment to discover what works best for you. I currently take around 1/10 tablet methyl B12 twice daily, morning and afternoon, plus 1/20 tablet adenosyl B12 afternoon. Approximate cost: $0.10 USD per day.

If you'd rather a simpler, once-a-day B12 supplement:

  • Easy dosage. ~250-500 mcg methyl B12 daily. Take 1/4 to 1/2 tablet Enzymatic Therapy B12 Infusion once a day. Place under upper lip to dissolve. Break, bite, or cut the tablets into halves or quarters as needed. Raise or lower dosage as needed. Approximate cost: $0.05 - $0.10 USD per day.
  • Even easier dosage. 1000 mcg methyl B12 daily. Take 1 whole tablet Enzymatic Therapy B12 Infusion once a day. To increase absorption, chew slowly and thoroughly before swallowing. Take with a meal. I've spoken with a few people who'd rather not chop up tablets into tiny bits and place them under the lip. Despite less efficient absorption, it should be fine to take a whole tablet and chew it, as the label suggests. If chewing 1 tablet a day helps, you could try twice a day, either with a whole tablet each time or with biting the tablet in half. Approximate cost: $0.20 USD per day.

And if you want to try an even greater dose, with sustained release and higher absorption rate:

  • Extra-strong dosage. ~2500 mcg daily. Use B12 Oils Adenosyl Methyl Oil. 1 spray on skin. I haven't yet tried the extra-strong dosage. Approximate cost: $1.00 USD per day.

Why Absorption in the Mouth or Skin Instead of Swallowing?

The natural intestinal absorption mechanism for vitamin B12 is intricate:

  1. The mouth secretes transcobalamin-I (TCN1) protein.
  2. Stomach acid frees the B12 in food (not necessary for supplements). TCN1 binds and protects the B12.
  3. The stomach secretes intrinsic factor (IF) protein.
  4. Pancreatic enzymes in the small intestine free the B12 from TCN1. IF binds the B12.
  5. The B12 is actively absorbed in the small intestine only if bound to IF. Saturation of absorption through IF is 1.5 mcg of B12 every few hours.
  6. Additional B12 is absorbed in the small intestine by diffusion at a rate of about 1% absorption.
  7. The intestine secretes transcobalamin-II (TCN2) protein. TCN2 binds and protects the B12 for transport through the body.

The net absorption of B12, if all steps are working well, is 1.5 mcg + (dosage / 100). (Surendran 2018; Nickfox 2016; Oh 2003; Allen 1978; Abels 1959). Because of the very small amount of B12 that can be actively absorbed with each meal, if you swallow your B12 supplement, it's especially important to divide the dosage and take it with multiple different meals each day.

For many people who need B12, the absorption process may be impaired at one step or another. Absorption through the mouth's membranes bypasses most of the digestion and absoprtion process. (Obersby 2015.)

More B12 will reach the cells if the tablet stays in the mouth for longer and dissolves slowly. If the tablet stays for 45 to 120 minutes below the upper lip, absorption may be 10-30% (Freddd 2013). I usually find the tablet doesn't last that long, but still has a strong effect even if it's fully dissolved in a few minutes.

The higher of the two suggested levels, "strong dosage," should be enough to saturate the TCN2 transport protein and allow additional B12 to enter the cells directly by diffusion. The additional B12 will enter the cell already in its active form, methyl B12 or adenosyl B12. That way, the cell is spared the energy and resources required to make the B12 into the form it needs, methyl B12 or adenosyl B12. (Freddd 2013.)

Absorption of B12 oils through the skin (transdermal) has been reported to allow up to 80% absorption rates (Garyfritz 2014).

WARNING: Watch Out for Low Potassium

If strange things happen when you take B12, stop the B12 or reduce the dose until you figure it out.

One way to reduce the dose is to swallow the same amount of B12 instead of placing it under the upper lip. That way, a trickle is absorbed so your body will have at least some B12.

If your body gets B12 after missing it, lots of processes can start up at once. Then other vitamins, electrolytes, other minerals, and even protein or glucose could run low. The body's chemical processes are making up for lost time and might need more of various nutrients. This is called "Refeeding Syndrome." It often occurs around the third day after starting a new supplement. (Freddd 2015.)

The most commonly depleted nutrient is potassium. Low potassium is dangerous. Symptoms I've observed myself (following higher dosages of B12) include muscle cramps, muscle twitches, fast heartbeat, heart skipping beats, constipation, and irritability. Other possible low-potassium symptoms include high blood pressure, dizzy spells, mood swings, and itching. (Freddd 2017.) In my experience, low potassium symptoms will resolve within minutes of taking a potassium supplement or within a day or two of cutting down B12 and eating lots of fruits and vegetables.

Some people might want to be prepared with a potassium supplement on hand. I use NOW brand potassium gluconate powder. I've always tended toward low potassium. A teaspoon a day (~533 mg potassium) of potassium gluconate powder seems to keep the low potassium symptoms away. I usually take the potassium powder in water, divided in 2 parts, morning and evening.

If you don't have a potassium supplement handy, you could temporarily stop the B12 if potassium symptoms develop. Then once you feel better, you could resume the B12 at lower dosage.

Other nutrients aside from potassium which support B12 metabolism include: magnesium, methyl folate, and L-carnitine; B1, B2, and other vitamins; boron, copper, zinc, selenium, molybdenum, iodine, and other minerals (Russell-Jones 2014; Freddd 2017). Some people might do better with additional supplements to support B12's functions. However, many plant-eaters might do fine with only the B12 supplement to complement a healthy plant-based diet.

The suggested B12 supplements are very strong. Though the bits are tiny, if the B12 supplement seems like too much, you might consider either swallowing the B12 to reduce absorption or taking an even smaller dosage.

Why Smaller B12 Dosages More Often?

After years of experimenting and thinking about vitamin B12, I'd suggest taking smaller amounts, more often. Frequent tiny amounts absorbed is our natural way of handling B12, from back when B12 was abundant in soils and plants.

Timing of B12 Supplement Relative to Sleep

Some people may find a B12 supplement too energizing for late in the day. Others, including me, may sleep better when taking it late in the day. In fact, for years, I went to sleep with a piece of methyl B12 under my lip, and slept better. Now, it seems to keep me awake if I do. You'll have to experiment to see what timing works best for you.