The Nottingham Trent University and University of Warwick research argues a major contributing factor to vitamin B12 deficiency is an increasing dependence on ultra-processed foods.

Dr Adaikala Antonysunil, a scientist in Nottingham Trent University's School of Science and Technology, said: ‘Our findings highlight the importance of monitoring and improving vitamin B12 levels before and during pregnancy to protect long-term health.

‘We recommend maintaining a balanced diet rich in fruits, vegetables, and other whole foods, while limiting ultra-processed foods. This can help to maintain adequate B12 levels and reduce future health risks.'

Globally, more than half (60%) of pregnant women are overweight or obese, leading to risks for adverse pregnancies and other metabolic health issues.

The researchers highlighted vegetarians and vegans were at a  higher risk of deficiency as Vitamin B12 is not naturally present in plant-based foods.

The study was co-authored by Professor Philip McTernan, from De Montfort University and was published in the journal BMC Medicine.