Removing vitamin D from the diet of healthy adult mice caused a significant drop in their ability to remember and learn, which researchers said was due to a pronounced reduction in perineuronal nets in the hippocampus.

The findings, published online in Trends in Neurosciences, may explain why vitamin D is vital for brain health and how deficiency can lead to schizophrenia and depression.

“As neurons in the hippocampus lose their supportive perineuronal nets,” he added, “they have trouble maintaining connections, and this ultimately leads to a loss of cognitive function.”