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Supplement advice for New Year vegans

An expert group co-founded by an Addenbrooke’s clinician has issued a “cautionary message” to those thinking of moving to a plant-based diet this January.

Dr Julian Owen head and shoulders
Mr Julian Owen

The group, ‘cluB-12’, chaired by consultant trauma and orthopaedic surgeon Mr Julian Owen, outlines its concerns it in a paper just published in the peer-led European Journal of Nutrition (opens in a new tab).

The paper, a collaboration between more than 20 experts from around the world, highlights that vitamin B12 is an essential nutrient that is absent from unfortified plant-based foods.

It encourages those moving to a vegan diet in 2023 to take a certified supplement of the vitamin at mealtimes and seek professional help should any symptoms occur relating to possible B12 deficiency.

Signs may include cognitive changes like depression, memory impairment, confusion, psychosis, tiredness and shortness of breath, and neurological complications leading to issues like muscle weakness or loss of mental and physical drive.

While applauding healthy and environmentally friendly lifestyles, the group warns most at risk are women of child-bearing age, pregnant and lactating, and vegetarians who are transitioning to a vegan diet.


The paper says: “The UK's recommended nutrient intake (RNI) for vitamin B12 is currently set at 1.5 μg/day (micrograms) for adults and is unaltered for pregnancy. However, this differs in the USA, where the RNI for adults is 2.4 μg/day and is modified for pregnant and lactating women to 2.6 and 2.8 μg/day, respectively."

“Within the European Union, the estimated average requirement (EAR) is 4 μg/day for adults and increases for pregnant and lactating women to 4.5 and 5 μg/day, respectively."

Thus, the current UK recommendations for vitamin B12 are both inadequate and incomplete. Not only are they significantly lower than in other developed countries, but they are also unaltered for different at-risk population groups.


The paper concludes:

Vitamin B12 is an essential nutrient that is absent from unfortified plant-based foods. We have aimed to provide a cautionary note on the importance of vitamin B12 to those individuals seeking to adopt a plant-based diet and in particular a vegan diet.


“An appropriately planned vegan diet has the potential to uphold a healthy and sustainable life, but consideration of a complete diet is essential.”

Vitamin B12 is an integral cofactor for two vital cellular metabolic reactions and is essential for the synthesis of blood cells and brain nerve tissue.

The usual dietary sources of vitamin B12 are animal foods; meat, milk, egg, fish, and shellfish. Vitamin B12 in eggs seems to be poorly absorbed relative to other animal food products