Algae – the missing ingredient in healthy vegan diets?

With the popularity of meat- and dairy-free diets continuing to grow globally, more people are being potentially exposed to a vitamin deficiency, with many experiencing a lack of vitamin B12 which plays a key role in blood and nerve cell manufacture.

New research by Cambridge University has unearthed a unique solution to the problem with algae proving to have a remarkable ability to accumulate quantities of B12.

It is thought that this could now be exploited to provide effective supplements of the vitamin.

Vitamin B12 is an essential micronutrient.

Lack of it triggers muscle weakness, numbness, nausea, weight loss, fatigue and increased heart rate, while continued deficiency will eventually leave people susceptible to ailments that include pernicious anaemia, heart disease and diabetes.

Supplements based on vitamin B12 are already available but, as it isn’t found in plants, meat is the main traditional source, along with dairy products and eggs.

“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,” said Prof Alison Smith, head of the plant metabolism group at Cambridge University.

As part of their research, Smith’s group has demonstrated how algae accumulate B12. “They don’t make it themselves, they take it up from their surroundings, where it is made by bacteria,” she said.

“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 tackle the serious problem that we are now facing over B12 deficiency.”

It is estimated that the total number of vegans in the UK has grown to more than one million, almost 1.5 per cent of the country’s population. This rise is reflected in sales of plant-based foods, which increased by 49 per cent between 2018 and 2020 but have now levelled off.

However, vegan diets supply only 10 per cent of the B12 that is provided by a standard UK diet.

This typically 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 a recent paper in the European Journal of Nutrition.

The study also pinpointed pregnant and lactating women, as well as older people, as now being at particular risk.

Related: Plant-based diet could cut bowel cancer risk in men by 22 per cent