Vitamin B12 – The Energy Vitamin

I started this series of posts as I got into researching the vegan diet in more depth. The information below comes from a range of websites including: vegansociety.com, vegan.com, veganhealth.org, the UK NHS website, US NIH website, healthline.com, and a number of other seemingly credible looking websites. Please note however that I am neither a doctor, a dietician, nor a nutritionist so if you are experiencing any health issues, it is always best to seek proper advice from a qualified professional.

What is B12, and why is it so important?

Vitamin B12 has many essential functions in your body and is necessary for keeping your nerves healthy, supporting the production of DNA and red blood cells, as well as maintaining normal brain function. It is often cited as main vitamin vegan’s really need to take as a supplement. However studies have also shown that perhaps as many as 6% of people in the US and UK aged 60 or older have vitamin B12 deficiency, while about 20% have low or borderline deficient levels. Some of the factors for deficiency include diet and age, with the ability to absorb this vitamin decreasing with age. It is also believed some conditions that interfere with nutrient absorption such as celiac disease, also affect B12 levels.

B12 deficiency can be slow to develop, and can be confused for other conditions. Symptoms may include: numbness or tingling in the hands, legs or feet, anaemia, weakness or fatigue, or difficulty with thinking or memory. B12 deficiency can be confused with iron deficiency as both can result in anaemia. A B12 deficiency can be treated with a series of high dose injections, but some studies say the damage done before treatment is commenced can be long-lasting.

Vitamin B12 is produced by bacteria in the gut of animals, whilst it is inherently vegan in itself (coming from bacteria), there are no known plant-based sources of B12. I did read somewhere that due to modern farming practices many animals are now fed B12 supplements themselves, but I didn’t fact-check this as being true or just vegan propaganda! I also read of some people eating soil to try and get B12 into their diet, please don’t try that.

Recommended Intake of B12

The Reference Daily Intake (RDI) from WHO and in the US for adults below 60 years of age is 2.4 mcg, Germany recommends 3 mcg. This seems like a very small amount, and hence this vitamin has been overlooked in the past, but that tiny amount packs a serious punch.

Meat-eaters consume B12 that is stored in animal flesh. For vegetarians and vegans, plant-based food sources include fortified breakfast cereals, UK and NZ marmite (but not Vegemite) and fortified plant-based milks. Nutritional yeast is also often fortified with B12.

In terms of the dosage available from fortified foods: a serving of Marmite has 1.9 mcg, a cup of soy milk has around 2.1 mcg, a serving of Kellog’s cornflakes has 0.63 mcg. To get adequate B12 from food sources it is recommended to have around 3.0 mcg at least twice a day, as it is estimated that the body absorbs only about 50% of B12 ingested in small doses. If you are not able to get this average level from food sources, which will be most vegans, a supplement is recommended.

The Vegan Society (UK) recommends either a 10 mcg supplement daily, or a 2,000 mcg supplement weekly. Veganhealth.org has a similar recommendation of 25-100 mcg daily or 1,000 mcg twice a week. The higher doses required for supplements are due to the absorption rates lowering as doses increase. The body can store B12 in the liver for short periods, hence a weekly dose is considered to be acceptable, but B12 is not stored well over the longer term. There seem to be no known side-effects from taking too much B12, but most advice as with everything, is not to overdo it.

Before researching this article, I had no idea this little known vitamin is so important for good health, and is something I probably should have paid more attention to even as a vegetarian. I have decided to take a weekly supplement as locally produced Indonesian muesli and granola’s and plant-milks are not usually fortified.

I hope this article was useful as a quick summary of the key facts and has started you thinking about your own B12 sources. If you want to read more, there are many resources online. Some do give conflicting advice, so please read from more than one source, and try and check where their data is sourced from. But suffice to say, the advice from everyone credible in nutrition, is certainly to take this one seriously, and even if you take no other supplements to consider B12. If you are at all in doubt about your B12 levels and needs, and whether you may be suffering a deficiency, then please do get a proper blood test done and advice from your doctor, as every situation is different.

Stay safe and healthy everyone!

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