A new study has identified a compelling link between vitamin B12 deficiency and chronic inflammation, which is associated with a range of health problems including cardiovascular disease, diabetes and neurodegenerative disorders.

Published in the Journal of the Science of Food and Agriculture, the research examined the effects of circulating B12 concentration on the levels of two key inflammatory markers in both humans and experimental models.

A team of researchers in Spain have investigated the effects of vitamin B12 on the levels of two molecules in the body which promote inflammation, specifically interleukin (IL)-6 and C-reactive protein (CRP).

Rosa M Lamuela-Raventos, professor of nutrition, food sciences and gastronomy at INSA-University of Barcelona and Ines Dominguez Lopez, a predoctoral researcher at the University of Barcelona led the study published in the Journal of the Science of Food and Agriculture.

They utilised samples from a randomised subsection of participants in a large clinical trial based in Spain, designed to assess the effect of the Mediterranean diet on the primary prevention of cardiovascular disease. 

An assessment of the serum levels of vitamin B12 and the concentrations of the inflammatory markers revealed a correlation between the two.

“Our study found that in general, the more vitamin B12 an individual has, the lower their inflammatory markers are -- we call this an inverse relationship”, explained Marta Kovatcheva, a postdoctoral researcher at the Institute for Research in Biomedicine (IRB Barcelona).

“We already know that vitamin B12 deficiency can be harmful in many ways, but what we have reported here is a novel relationship. This might help us better understand why some unexplained symptoms of human B12 deficiency, like neurologic defects, occur,” the authors wrote.

Surprisingly, the researchers noted that, unlike humans, experimental models do not become B12 deficient with age. 

“We didn't know this before, and it poses the possibility that studying experimental models could potentially help us understand how we could prevent B12 deficiency in older humans,” said Kovatcheva.

The team now hopes to explore the link between vitamin B12 and inflammation, within the context of specific high-inflammation conditions, such as infection, obesity, and irritable bowel syndrome.