• B12 is really important for lots of different biological processes.
  • There are plant based sources of B12 but not in quantaties that are practical for meeting daily recommended intake needs.
  • B12 dificiency can lead to very serious health problems but this can be easily overcome by making sure you get enough B12 through supplimentation.

Take Home Message

Vegans really should be taking a reliable source of B12 supplimentation.

Paper's Stats

Table describing cobalamin content in vegetable foods.It seems that X-mas has come early for us vegans! What more could we hope for this holiday season than a comprehensive scientific review of B12. Happy days!!

Despite my excitement I must confess to skimming through this paper. I found it to be a bit dry because it’s packed full of information! So I’m just going to summarise some of the main points I took away from it and leave all you eager vegans out there can read it in full!!

The main points:

  • B12, also known as cobalamin, is super important to many critical biological processes in our bodies. This includes, DNA synthesis, intense cell replication, and maintenance of myelin sheaths in neurons.
  • B12 helps remove potentially harmful molecules from our bodies, like cyanide (which is found in trace amounts in lots of foods).  
  • Recommended daily intake of B12 depends on the authorising body but ranges between 2.4 – 8.6 μg/day.
  • Pregnant and breastfeeding women need higher daily levels of B12 to help with fetus/baby development.
  • Vegans are at an increased risk of being deficient in B12 but this can be managed easily with supplementation (we all knew that!).
  • Most countries consider someone to be deficient in B12 if their serum concentrations are lower than about 150 pmol/L, but this ranges between <110 – <250 pmol/L.
  • There are plant-based sources of B12 (this is something I learnt!), but very few foods have been tested and the levels are generally too low to be considered a viable source for daily intake needs. For instance, there is B12 in shiitake mushrooms but your would have to eat 50g (dry weight) every day to possibly get the adequate levels of B12. Not sure about you but I don’t think my wallet could handle it!!
  • The other issue with plant source is that very few studies have looked at the absorption of B12 from plant sources, which means even less B12 might be available that what is simply in the source (this is the bioavailability of the vitamin, which refers to the total amount your body can actually absorb, not just the amount that you ingest).
  • B12 deficiency probably won’t be picked up until its late stages through signs like, neuropsychiatric abnormalities, neuropathy, dementia, and atrophy of optic nerves (though this last one is rare).

So basically the research suggests that vegans should take a B12 supplement to stay healthy! And if in doubt maybe see your doctor and get your levels checked.

Have fun reading this one. Let me know if I missed anything that you think is super important or interesting.

Title: Vitamin B12 among Vegetarians: Status, Assessment and Supplementation

Authors: Gianluca Rizzo, Antonio Simone Laganà, Agnese Maria Chiara Rapisarda, Gioacchina Maria Grazia La Ferrera, Massimo Buscema, Paola Rossetti, Angela Nigro, Vincenzo Muscia, Gaetano Valenti, Fabrizio Sapia, Giuseppe Sarpietro, Micol Zigarelli and Salvatore Giovanni Vitale

Journal: Nutrients

Date Published: November 29, 2016


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Research Type

Peer-reviewed research

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