All about vitamin B: sources & benefitssuperfoodsvegan B12cookingsproutingfermentingsupplements

B vitamins are water soluble. This means the body cannot store them, so we need to ensure an adequate supply every day. Although our bodies can’t make B vitamins, our gut flora can to some degree. As it’s difficult to measure their contribution, it makes more sense to focus on providing ourselves with nutrients from our food as much as possible.

From the chart below we can see how important B vitamins are if we’re to function at optimal level. Their role in providing energy, regeneration of cells, controlling DNA and RNA is crucial, and they have a very important part to play in keeping the nervous system healthy.

B Vitamins on a plant-based diet

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As you’ll see from the chart, one very important factor is the stability of B vitamins. Some are sensitive to light, heat and/or ph conditions, so storage and preparation of food ingredients needs to be considered carefully, as does the storage of any supplements.

What exactly is a vitamin?

Definition: Any of a group of organic compounds which are essential for normal growth and nutrition and are required in small quantities in the diet because they cannot be synthesized by the body.

Origin: early 20th century: from Latin vita ‘life’+ amine, because vitamins were originally thought to contain an amino acid.

Oxford Dictionary


B-rich superfood #1: algae (including seaweed)

Two types of powdered algae are especially useful to boost your B vitamin intake. Spirulina is rich in B1, B2 and B3. Chlorella is rich in B2, B3 and B12 (see B12 below). You can add them to smoothies and juices, or just take them in water.

Seaweed is rich in B vitamins. Be careful about using too much uncooked seaweed though, as it’s high in iodine. Many of us in the West are low in iodine, so might benefit from a boost, but if you have a thyroid condition be especially cautious, as it can affect thyroxine levels (1).

Dried seaweed can be added to smoothies or sprinkled on salads. It can also be used widely in cooking, but that will affect the B vitamin levels (see cooking below). Kelp and dulse are both native to the UK, and are available from The Cornish Seaweed Company. All their products are certified organic and sustainably sourced. We use them every day 🙂

B-rich superfood #2: nutritional yeast

Nutritional yeast is widely believed to have a high B12 content, but that’s not quite true in its natural state – it’s often fortified with B12. Nutritional yeast is a great source of B vitamins in general though, as well as many other nutrients. It’s easy to sprinkle on salads, or pretty much any savoury dish.

Don’t let the word ‘yeast’ put you off – this kind of yeast is non-active, so it’s considered fine on an anti-candida or similar diet. Kimberly Snyder has a great article with stacks more information.

Organic vegan nutritional yeast is hard to track down, but there’s one sort made by Marigold. You could ask your local health food shop to order it for you, or you can get it online from RealFoods. Note that the organic version is not fortified with B12.

The trouble with vegan B12

The only plant-based food source of true B12 seems to be chlorella, but it’s unlikely that it can practically supply enough (2). While the RDA for B12 is 2-3mcg, which is around 2-3g of chlorella, no studies have yet been carried out to prove this is sufficient to prevent B12 deficiency.

Bacteria in the gut synthesise B12, but in a different area to where absorption takes place, thus not providing a source of the vitamin.

Many vegans thus take B12 supplements.

Effects of cooking on vitamin B

When considering the nutrient content of any food, it’s important to take bioavailability into account. For example, while legumes contain good levels of vitamin B in their raw state, obviously we generally cook them. This makes them safer and more readily digestible, but it also lowers their B value.

Let’s have a look at mung beans as an illustration. The dark bars show the beans in their raw dry state, and the pale bars show the loss in cooking. We’re making the assumption they’ll roughly double in size due to the water intake, so 1g becomes 2g.

You’ll see that only B2 really stays intact, while the rest are lost by an average of almost 50%. Folate (B9) is not shown, but is lost by almost 70%.

Effects of cooking on vitamin B in mung beans

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Effects of sprouting on vitamin B

Now let’s stick with mung beans, and see what happens when we sprout them instead of cooking. The dark bars show the beans in their raw dry state, while the pale bars show the increase when sprouted. You’ll see that B1 and B6 show a moderate increase, while B2 increases by a whopping 425%, B3 by 200%, B5 by just over 100% and B7 by 290%.

Effects of sprouting on vitamin B in mung beans

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These figures are from an old study, so you’ll notice discrepancies in the raw values compared to the cooking example above. Every study will come up with slightly different results anyway, so they can be taken with a pinch of salt. This is just meant as an interesting illustration of how powerfully the preparation of food can affect its nutritional value – for better or worse.

Effects of fermenting on vitamin B

Another way to increase the B vitamin value of raw foods is to ferment them, or to buy fermented foods such as kimchi and sauerkraut. The lactic acid bacteria that multiply during fermentation produce a variety of B vitamins. Certain strains have been shown to specialise in creating different nutrients, so generally the wider the spectrum of beneficial bacteria, the wider the spectrum of nutrients they provide. Bifidobacteria are said to be especially good at increasing B vitamin content (3).

Again, bioavailability is key. Some alcoholic drinks, for example, may have a high B content, while their overall effect is actually to deplete B vitamins in the body.

More about fermenting »

Vitamin B supplements

Of course it’s always ideal to try and get the nutrients you need from food, but supplements can be a useful addition to the diet – however healthy – especially in cases of chronic illnesses or stress. They can also be beneficial for the elderly, who can sometimes have a reduced ability to absorb vitamins.

Because they can’t be stored in the body, any surplus B vitamins will be flushed out. This makes it difficult to actually overdose, so supplements can be taken safely if you think your intake needs a boost.

Vitamin B mysteries unravelled

  • There used to be more B vitamins listed but some were found not to be true vitamins – hence some missing numbers
  • B2 (riboflavin) used to be called lactoflavin (from milk), ovoflavin (from eggs), heptoflavin (from liver) and verdoflavin (from plants)
  • Niacin (B3) used to be called PP factor (pellagra preventative factor)
  • Folic acid is also known as folacin, vitamin Bc, vitamin B9, and lactobacillus casei factor



How to get more vitamin B into (and out of) your diet?

  • Consume a variety of good plant-based sources throughout the day
  • Consider adding small amounts of B-rich superfoods, such as nutritional yeast, chlorella, spirulina, kelp and dulse
  • Be aware of how cooking and storage can degrade B vitamins
  • Consider sprouting
  • Consider fermenting
  • As a last resort (but an important consideration), take supplements where necessary

Got any tips or questions of your own about B vitamins? Leave us a comment below, we’d love to hear from you.


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