Vitamin B12 is important for the healthy production of red blood cells, and for keeping your body’s nerves in good physical shape.
Vitamin B12 also builds DNA, and can help prevent a type of anaemia which makes people tired and weak.1
Unfortunately though, your body does not make this vitamin, nor does it convert it over from other nutrients. So you have to consume it in some form or another.
Well, technically, you do produce B12 in your digestive tract, which means you excrete it rather than absorbing it.2
Your body also does not store this vitamin, so your consumption of it should be fairly regular.3
Vitamin B12 deficiency
A deficiency of vitamin B12 or folate (which works hand in hand with B12) can manifest as extreme tiredness, a lack of energy, pins and needles, a red and sore tongue, mouth ulcers, muscle weakness, disturbed vision, and mental or emotional issues like depression, confusion, and problems with your memory or your judgement.4
Because vitamin B12 is almost exclusively found in animal sources such as milk, eggs, cheese, fish, beef, and chicken, it can be hard for vegans (or vegetarians who eat low amounts of milk and eggs) to get enough.5
So what are the alternatives then? We take a look at three ways in which vegans can get more B12 in their diet:
Non-animal sources of vitamin B12
Though B12 mostly comes from animal products, you can also get it in yeast extract (that is, Marmite or Vegemite).6 Some mushrooms and algae also contain vitamin B12.
One plant source of B12 is nori. This is the flat, edible seaweed used for sushi. To meet your daily requirements, you may only have to consume four grams of dried nori.7
One warning with nori however is that its B12 content actually comes from microorganisms which live on it, so the amount of B12 it contains, if any, would depend on the conditions it was grown in.8
Aside from sushi, you can munch on nori directly (after getting it from an Asian market, or online, for example), and you can add flakes of it to noodle soups, salads, rice bowls, and tofu.
Shitake mushrooms also contain B12, though not a lot. To meet your daily needs, you would have to consume around 50 grams of the dried mushroom every day.9
In general, it is best to get your vitamins from a variety of sources, so if you are a vegan, you could always alternate between mushroom, nori, and marmite days.
You could also combined such consumption with the below two options: fortified foods and supplements.
Foods fortified with vitamin B12
Some foods are specially fortified with vitamin B12.
Nutritional yeast, a species of yeast known as Saccharomyces cerevisiae which is used to bake bread and brew beer, often contains added B12.10
Nutritional yeast can also provide an extra depth of flavour to your cooking.
You can add a tablespoon of it to sauces, chillies, curries, or even sprinkled on popcorn, to meet all of your daily intake needs.11
There are also breakfast cereals which contain a significant portion of the daily recommended intake of B12.
Check their packaging to find out if they do, and how much.
Non-dairy milk, meat substitutes, and vegan spreads may also be fortified with vitamin B12.12
The advantage of foods fortified with this vitamin is that they are also typically easy for your body to digest, meaning they have high bioavailability and are a good source of B12.13
Vitamin B12 supplements
When there is a noticeable B12 deficiency, the supplement is often given by injection at first.
Then, if the deficiency is diet related, you can either consume supplement tablets between meals, or get regular injections.14 Vitamin B12 supplements are now also available as an oral spray.
You can get vegan B12 supplements quite easily. One way you can meet your daily requirement for B12 is to combine a supplement with a few fortified foods a day.15
B12 pills come in two forms; the natural form (methylcobalamin), and the synthetic form (cyanocobalamin).
Professionals recommend the natural form, just because the synthetic form may impair kidney function for people who have borderline kidney problems.
The supplement is safe to take even if you have reduced stomach acid. It is not food-bound, so you do not need stomach acid to absorb it.
Older people are particularly recommended to take a supplement, if they are not able to get enough vitamin B12 or are showing symptoms of a deficiency.
You need a recommended amount of around 2.3 micrograms a day.16
Last updated: 16 April 2021