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Thorne Research, Bio-B12, 60 Vegetarian Capsules (Discontinued Item)

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Thorne Research, Bio-B12, 60 Vegetarian Capsules (Discontinued Item)

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Thorne Research, Bio-B12, 60 Vegetarian Capsules (Discontinued Item)

Out of Stock - Discontinued
  • Shipping Weight:
    0.08 lbs
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  • Product Code: THR-12003
  • UPC Code: 693749120032
  • Package Quantity: 60 Veggie Caps
  • Dimensions:
    1.8 x 1.8 x 3.3 in, 0.05 lbs
    Switch to Metric units

Product Rank:

Frequently Purchased Together
Product Overview


  • Dietary Supplement
  • Hypoallergenic

In order for vitamin B12 to be absorbed in the gastrointestinal tract, it first needs to be bound in the stomach to a protein called R-protein. In the intestines pancreatic proteases cause the R-protein to release vitamin B12 to bind with intrinsic factor, making it absorbable. Thorne Research's Bio-B12 contains methylcobalamin (an active form of vitamin B12) and 5-MTHF (an active form of folate) in a base of papain. Papain is a potent protein-digesting enzyme from papaya that also results in the release of vitamin B12 from the R-protein, thus facilitating the absorption process. Zinc picolinate is included for support of the pancreas, which produces other digestive enzymes that facilitate the absorption process.

Methylcobalamin (an active form of vitamin B12) is essential for recycling homocysteine and the formation of methyl donors involved in cardiovascular function, sleep, blood cell formation, and nerve function. Most vitamin B12 supplements contain cyanocobalamin; however, the liver must first "detoxify" the cyanide molecule and attach a methyl group to form methylcobalamin from the cyanocobalamin. Methylcobalamin is already in the biologically active, tissue-ready form. Evidence indicates the body utilizes methylcobalamin more efficiently than it does cyanocobalamin. Research shows the quantity of cobalamin detected following a small oral dose of methylcobalamin is similar to the amount following administration of cyanocobalamin; but significantly more cobalamin accumulates in liver tissue following administration of methylcobalamin. Human urinary excretion of methylcobalamin is about one-third that of a similar dose of cyanocobalamin, indicating substantially greater tissue retention.

Suggested Use

Take 1 capsule one to three times daily or as recommended by your health-care practitioner.

Other Ingredients

Hypromellose (derived from cellulose) capsule, microcrystalline cellulose, silicon dioxide.


Tamper Evident: Use only if bottle is sealed. Store tightly sealed in a cool, dry place.

If pregnant, consult your health-care practitioner before using this product.


While iHerb strives to ensure the accuracy of its product images and information, some manufacturing changes to packaging and/or ingredients may be pending update on our site. Although items may occasionally ship with alternate packaging, freshness is always guaranteed. We recommend that you read labels, warnings and directions of all products before use and not rely solely on the information provided by iHerb.
Supplement Facts
Serving Size: One Capsule
Each Capsule Contains: Amount Per Serving % DV
Vitamin B12 (as methylcobalamin) 1 mg 16,667%
Folate (as L-5-Methyltetrahydrofolate† from L-5-Methyltetrahydrofolic Acid, Glucosamine Salt) 800 mcg 200%
Zinc (as Zinc Picolinate) 15 mg 100%
Papain†† 75 mg *
*Daily Value (DV) not established.
†This product uses Gnosis S.p.A.'s L-5-Methyltetrahydrofolic Acid, Glucosamine Salt (Quatrefolic).
††An enzyme derived from Papaya (Carica papaya).
iHerb Customer Reviews


Posted by Rena61 on January 14 2018 | Verified Purchase

I still prefer more of a balance of Multi vitamin vs single targets.

Thanks for your feedback!

Excellent but Changed

Posted by iHerb Customer on January 9 2018 | Verified Purchase

I lived a much more productive life thanks to two bottles of Bio B12 a month. I was devastated when no one had it this month. I had to accept an inferior product. After going to the manufacturers site I learned the Bio B12 does not show up in search only Methylcobalamin. This formula is not Bio B12. It eliminates the other ingredients that made this special plus is not hypoallergenic. It is no different than other companies Methylcobalamin based B12 formulas now. I am VERY disappointed with Thorne Research. Yes we can buy each of the other ingredients as separate supplements or try B complex for tge additional ingredients, but the B complex can be too much of other Bs for some of us. As if supplements are not spendy enough now instead of 4 a day I will need to take two more supplements and look around until I find ones I can deal with inactive ingredients in Shame upon you Thorne Research. My only hope is that perhaps Thorne is out of it too or reformulating to give more in each capsule, but as of now, do not expect this to be back in stock anywhere. If you find any, snatch it up fast

Thanks for your feedback!

Ineffective if you're B12 defficient

Posted by iHerb Customer on September 17 2017 | Verified Purchase

I needed to take at least 4 tablets a day to notice any effect at all - I don't know anyone that likes to take more than 2 tablets a day let alone 4! I needed to reorder a higher dose. Feel like I wasted my money.

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One of the best B12 supplements on the market!

Posted by iHerb Customer on August 14 2017 | Verified Purchase

I am a health coach and detoxification specialist that is always looking for the best supplements in the world and this B12 supplement by Thorne Research is one of the best in the world because it contains methylcobalamin which is a type of b12 found in nature unlike cyanocobalamin which is made from cyanide. It also contains nutrients specifically added to make sure your absorbing the B12 because without the intrinsic factor working correctly in the body which almost no ones is, you will not absorb b12 taken orally. It also contains co factor nutrients which help improve the uptake of the b12 and work synergistically to improve your health holistically.

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Posted by iHerb Customer on February 27 2017 | Verified Purchase

Being deficient in B12, I was taking a sublingual tablet (which eventually disturbed my mouth lining) and a B complex. This is a convenient way to cut down on the number of supplements you have to swallow.

Thanks for your feedback!