Vitamin B12 – who needs it?

Everyone needs a regular source of vitamin B12 and for vegans this means a supplement or a good supply of B12-fortified foods.  

What is B12 and why do we need it?

Vitamin B12 helps make red blood cells and keeps our nervous system healthy. A deficiency can cause serious problems, especially in the young, with symptoms including extreme tiredness, lack of energy, pins and needles, muscle weakness, depression and cognitive problems such as poor memory, understanding and judgement. It can lead to raised levels of a substance called homocysteine, which can increase the risk of heart disease and stroke. Serious stuff! 

How much do we need? 

Government guidelines recommend 1.5μg (micrograms) of B12 a day. A microgram is a millionth of a gram so we need only a tiny amount. But getting that small amount is vital.

What’s the beef with B12?

B12 is naturally made by bacteria in soil and water or is grown in vats for supplements. Traditionally, farmed animals got B12 from eating food from the ground but with so many now confined in factory farms, animals are fed B12 supplements. The notion that you need meat or dairy foods for B12 is a myth so you might as well cut out the middleman and take the supplements yourself!   

The B12 in meat and dairy is bound to animal protein, making it harder to absorb. In fact, absorption from animal foods is a complicated process that declines with age. As a consequence, up to 40 per cent of older people (regardless of diet) in the UK suffer from low B12. 

Too much of a good thing?

Vitamin B12 is water-soluble so if you take too much, it simply comes out in your in urine. Guidelines say that up to 2,000μg a day is unlikely to cause problems, but you shouldn’t take more than that. 

To meet your daily target you can breakfast on cereal and soya milk, making sure that both are fortified with B12, or Marmite (yeast extract) and toast. For lunch, try soup with Vecon stock and a roll, and for dinner, sprinkle a few Marigold Yeast Flakes fortified with B12 on whatever you’re eating – a 5g pinch contains more than 100 per cent of the recommended daily amount. It goes particularly well on pasta dishes and bakes. And for pudding – soya yoghurt or dessert with added B12. Contrary to common belief, fermented soya foods and seaweeds don’t provide B12.   

Topping up a few times a week with a supplement is a good safety net to ensure you’re getting enough. 

A well-planned, varied vegan diet, including B12-fortified foods and supplements, not only meets your requirements but provides a healthier source than meat or dairy, setting you up for a healthy old age. 

For more detailed information about vitamin B12 see our health feature Be sure about B12 and to find out more about vitamin B12 and other B vitamins generally, see Viva!Health's comprehensive A to Z of Nutrients


About the Author

Justine Butler

Dr. Justine Butler is the senior health researcher and writer at Viva! She joined as a health campaigner in 2005 after graduating from Bristol University with a PhD in molecular biology. She also holds a BSc in biochemistry, and a Diploma in nutrition.

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