People following a vegan diet will soon be encouraged to take algae supplements to prevent a B12 vitamin deficiency from developing, new research identifies.

Currently, plant-based diets suffer from a lack of B12, putting vegans at higher risk of developing a vitamin deficiency.

However, research conducted at Cambridge University has found that supplements made from algae may be the answer as the largely aquatic organisms can accumulate the vitamin B12 – a key nutrient involved in blood and nerve cell manufacture.

Top author Professor Alison Smith said: “Diets based purely on plant products are great on many levels, but they have certain deficiencies, and one of the most important of these is their lack of the vitamin B12.”

Joint author Dr Payam Mehrshahi said: “Supplements based on vitamin B12 are already available, but some are effective and others are not.

“If you are on a vegan diet, you are at risk of being vitamin B12 deficient. You can buy supplements but if you pick up the wrong tablet, the wrong supplement, then you could continue to cause yourself harm.”

Professor Smith added: “Many vegans would prefer not to have chemical supplements and they would like to get their B12 as a natural part of their diet.

“You cannot get it from plants but we have found that certain algae are rich sources of the vitamin.”

Symptoms of a vitamin B12 deficiency include weight loss, nausea, muscle weakness, fatigue, increased heart rate and muscle numbness.

If an individual lacks the vitamin B12 over a long period of time they are also at risk of developing pernicious anaemia, heart disease and type 2 diabetes.

Dr Mehrshahi said: “The crucial point is that B12 is made by bacteria such as those that grow in the digestive systems of cows and sheep.

“You cannot get it directly from plants. Meat has been the main traditional source along with dairy products and eggs.”

Dr Mehrshahi added: ““However, if you adopt a vegetarian diet, or more noticeably a vegan diet, your B12 intake can be drastically reduced, and that is now having noticeable consequences for the nation’s health.”

More than one million people in the UK follow a vegan lifestyle. Since 2018, the sale of vegan products has increased by 49%.

People following a vegan diet only receive 10% of the vitamin B12 that is provided by a standard UK diet.

The level works out at around 0.5 micrograms of B12 a day, a figure that is well below the level considered to be a healthy dose, according to diet experts.

Authors of a prior study have said: “This highlights an urgent demand for fortification of plant-based dairy and meat alternative foods in the UK, in particular to combat deficits in vitamin B12.”

Professor Smith noted: “We have identified that there are different forms of B12 and pinpointed which algae accumulate the varieties that work in humans.

“That means we can help industry start making effective algal supplements that should allow us to start to tackle the serious problem that we are now facing over B12 deficiency.”

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