Vitamin B12 (also referred to as cobalamin) is a really important nutrient for vegetarians, and especially vegans, to be aware of. This is because it is the only vitamin that cannot be found in plants. The UK government recommend an intake of 1.5μg (micrograms) per day for both male and female adults (British Nutrition Foundation, 2015).
Vitamin B12 is water soluble and 60% of B12 in the body is stored in the liver. These stores can last up to several years, and so after becoming vegan, it may be a year or two (or more) before initial signs of deficiency show, including fatigue and anaemia. Because it's an important vitamin for blood cell formation and the nervous system, further depletion can then lead to more severe features such as bone marrow suppression, abnormal reflexes, and memory loss.
So how can we make sure we're getting enough vitamin B12 in our diets? Well, vegetarians get some B12 from dairy and eggs, and many vegan foods are fortified with B12 - including breakfast cereals, spreads, nut milks, and some nutritional yeasts. The amounts vary from country to country and from brand to brand, so read the labels carefully.
Supplements are recommended for vegans who do not eat 2-3 fortified foods a day. B12, both in supplements and fortified foods, is simply sourced from culturing bacteria, which make B12 as a by-product. This is the same way that animals make B12 - the only difference is for them, the bacteria making it live inside their guts. So vegans get their B12 from the very same source as every other animal on the planet – micro-organisms! Getting your B12 from fortified foods or supplements doesn't cause suffering to animals, or cause environmental damage, so that's a win on every level.
Here is the amount of B12 recommended intake by The Vegan Society (2001):
- Eat fortified foods 2-3 times a day to provide 3μg per day
- OR take a daily B12 supplement providing at least 10μg
- OR take a weekly B12 supplement providing at least 2000μg
The reason they suggest the higher doses for the daily and weekly supplements is because B12 is absorbed better in small doses. So, the less frequently you obtain B12, the more you need to take.
Plant-based tip! Many meat eaters like to use B12 to criticise plant-based diets by saying that if vegans rely on a supplement, then their diet cannot be 'natural'. In fact, I find the opposite to be true, and I find being well informed and prepared very useful for when a debate on the topic might arise. So, here are my thoughts on why I am more than happy to take B12:
- There is also nothing 'natural' about factory farming (where 90% of meat comes from)
- Evolution is natural, and humans have evolved to use their intelligence to enable a cruelty-free and sustainable diet. Why not take advantage of this?
- Most people (over half the US adult population) take supplements, so why only call vegan diets ‘unnatural’?
I'd love to hear about any other stances you take when people try to criticise veganism on the grounds of requiring a supplement - leave your comments below!