Vitamin D deficiency may weaken supportive scaffolding in the brain thus causing neurons difficulty in maintaining connections, according to a study recently published in the journal Trends in Neuroscience.

These findings help to explain the established link between low levels of vitamin D and a person’s risk of developing the neurological symptoms of mental health conditions.

Vitamin D deficiency has been linked to a number of different psychological and neurological conditions various conditions. Furthermore, research has shown that depriving middle aged rodents of vitamin D led them to develop brain damage and perform more poorly on cognitive tests.

“Over a billion people worldwide are affected by vitamin D deficiency, and there is a well-established link between vitamin D deficiency and impaired cognition,” said Thomas Burne, an associate professor at the University of Queensland Brain Institute in St. Lucia, Australia. “Unfortunately, exactly how vitamin D influences brain structure and function is not well-understood, so it has remained unclear why deficiency causes problems.”

In this latest research, Burne deprived mice of dietary vitamin D for 20 weeks. He found that these mice were less likely to be able to learn and remember new things compared with mice in the control group.

Burne hypothesised that vitamin D makes perineuronal nets (PNNs) more vulnerable to the degrading actions of enzymes. PNNs act as scaffolding in the brain and play an important role in neuroplasticity, the brain’s ability to reorganise itself by forming new neural connections throughout life.

“These nets form a strong, supportive mesh around certain neurons, and in doing so, they stabilise the contacts these cells make with other neurons,” Burne explained. “There was also a stark reduction in both the number and strength of connections between neurons in [the hippocampus].”

These changes result in the loss of cognitive function, which could not only impair daily thinking and behaviour but also raise the risk of developing conditions such as dementia. Although more research is needed to confirm these findings in humans, this study makes a hugely important contribution to the literature in explaining the potential mechanisms behind the effects of vitamin D deficiency.