B12 #veganb12

The term alone, vitamin B12, gets thrown around left right and centre whenever someone mentions anything to do with a vegan diet.

What is vitamin B12 and what are its functions?

Vitamin B12 is a water-soluble vitamin important for the maintenance of the nervous system and in the process of the formation of red blood cells.

Vitamin B12 is only found in animal protein, right?

Wrong. It is true that vitamin B12 has a reputation of only being present in animals and that animals contain B12 naturally. However, this is in fact wrong. Both animals and humans must obtain it from bacteria, directly or indirectly. 

Vitamin B12 is bacteria you say?

Yes. It can be found in bacteria-laden manure and un-sanitised water. It can also be found in the human intestinal tract; however, it is not clear whether sufficient amounts are made and absorbed there to meet our nutritional needs.

The only reason that we get vitamin B12 through eating animal protein is because animals are exposed to this bacterium, through their food, water and living conditions. Not only are they exposed to the vitamin, but animal feed is commonly supplemented with vitamin B12 as well. So, animal protein, rumoured for being the only place to get vitamin B12 couldn't be more of a myth. The fact that the animals themselves need to have it supplemented into their diet just goes to show how inadequate our knowledge of B12 actually is.

Is the vitamin B12 from animals good?

Technically you're just receiving second hand vitamin B12, with the animal being the middle man. If that isn't enough to convince you to go straight to the source itself, the terrible living conditions farm animals endure result in most meats being contaminated with faecal bacteria, according to a recent report by Sofia Pineda Ochoa, MD (the co-founder of Meat Your Future, an educational non-profit that provides fact-based information about the health, environmental, and ethical implications of consuming animal products) could convince you.

Why don't we get vitamin B12 naturally then?

Historically humans have received adequate vitamin B12. How, you may ask? Through eating plant foods that have grown naturally in soil and been eaten, unwashed, with the nutrients from the soil still present on the food.

You see, the issue with our food today is that they are sanitised removing any potential contaminants and bacteria. Long story short, the food we are consuming contains no vitamins and minerals found in the soil and in turn we don't get the vitamin B12 from plant sources anymore. We also once drank at fresh water rivers and lakes which contained this bacterium. However, we now filter all of water and add chemicals to it which removes any traces of this vitamin.

In essence, our modern industrialised food systems means that we don't get natural access to vitamin B12, yet animals do as we tend not to care as much about the sanitisation of their food, water and living conditions. 

Do we absorb vitamin B12?

Simply put, we do, and we don’t. People eating animal protein still report having low levels of vitamin B12 and it’s unclear as to why. I mean there are hypotheses that because it is second-hand vitamin B12 which has been completely broken down by the time it enters our bodies. However, research suggests that the reason could be due to food cobalamin malabsorption.  Simply put our bodies, through various factors have a decreased ability to absorb nutrients from food. There are a number of lifestyle factors and ailments that effect the gastrointestinal tract, like alcoholism, smoking, and conditions which slow the movement of food through the gastrointestinal tract which all attribute to vitamin B12 deficiencies. Luckily, through various case studies, almost all humans are able to absorb the crystalline form of vitamin B12  found in supplements and fortified foods like nutritional yeast where the vitamin B12 is added. 

So, it is absorbed yes, however the effectiveness of absorption is varied. The best way to see whether you’re absorbing vitamin B12, or need to start supplementing it is to go a get a blood test.

So, is it necessary to eat animal products to get sufficient B12?

No, absolutely not. In fact, studies show that animal products increase our levels of IGF-1, TMAO as well as unhealthy heme-iron associated with oxidative stress and free radical formation. IGF-1 is a hormone constantly associated with increased cancer risk and tumour growth, and TMAO is a substance that injures the lining of our blood vessels and promotes the formation of cholesterol plaques. 

In fact, the recent past president of the American College of Cardiology, Dr. Kim Williams, stated during his tenure that the extensive medical evidence linking TMAO to cardiovascular disease was, in his opinion, “sufficient reason for people to avoid consuming all animal foods (even without considering all of the other highly problematic health issues associated with meat, dairy, and eggs).”

So, what happens when we become B12 deficient?

B12 helps in the formation of genetic material so naturally, a deficiency can impair our normal production of DNA. It can also result in problems with the maintenance of the nervous system, causing a wide variety of neuropsychiatric symptoms as well as anaemia through disrupting the normal production of red blood cells.

What can I do to ensure I am getting enough vitamin B12?

Getting regular blood tests will help you identify deficiencies and then you can experiment with how you absorb it the best. Oral supplements, B12 injections and fortified foods can all aid and ensure you don’t become deficient in the vitamin, as B12 is an important and necessary nutrient.


  1. Yamada K (2013). "Chapter 9. Cobalt: Its Role in Health and Disease". In Sigel A, Sigel H, Sigel RK (eds.). Interrelations between Essential Metal Ions and Human Diseases. Metal Ions in Life Sciences. 13. Springer. pp. 295–320. doi:1007/978-94-007-7500-8_9ISBN978-94-007-7499-5PMID 24470095.
  2. Frontiers in Nutrition (28 June 2019), Vitamin B12 Intake from Animal Foods, Biomarkers, and Health Aspects, retrieved 13 August 2019 from https://www.frontiersin.org/articles/10.3389/fnut.2019.00093/full
  3. Ochoa, S. (16 November 2017) Vitamin B12: All Your Questions Answered, retrieved 15 March 2019 from Forks Over Knives: https://www.forksoverknives.com/vitamin-b12-questions-answered-2/#gs.dv3lq6
  4. Walsh, S. (2004) What Every Vegan Should Know About Vitamin B12, retrieved 15 September 2019 from The Vegan Society: https://www.vegansociety.com/resources/nutrition-and-health/nutrients/vitamin-b12/what-every-vegan-should-know-about-vitamin-b12