Low pre-natal vitamin D doubles schizophrenia risk

Newborn babies with low levels of vitamin D have an increased risk of developing schizophrenia later in life, researchers at the Queensland Brain Institute have found.

The research team used tiny samples of blood taken as part of routine screening from newborn babies in Denmark. They then compared vitamin D concentrations in babies who later developed schizophrenia with healthy controls – and the study confirmed those with low vitamin D had a twofold increased risk of developing the disorder.

Vitamin D, or the "sunshine hormone", is the result of sunshine on the skin. It has long been known that it is important for healthy bones, but the Queensland team has discovered that it is also important for healthy brain growth.

Low vitamin D is common in many countries. Researchers have previously found that people with schizophrenia are more likely to be born in winter.

"While we need to replicate these findings, the study opens up the possibility that improving vitamin D levels in pregnant women and newborn babies could reduce the risk of later schizophrenia," investigator Professor John McGrath said.

Findings from the three-year study, published in today's edition of Archives of General Psychiatry, could eventually inform public health messages, in much the same way that pregnant women are encouraged to increase folate to reduce the risk of spina bifida in their children.

"While the links between vitamin D and bone growth have long been appreciated, the fact that we have discovered it is also important for healthy brain growth is a vital step forward," Professor McGrath said.

Fellow investigator Dr Darryl Eyles said: "Vitamin D is necessary for cell growth and communication in all organs in the body, so it's no surprise that a lack of vitamin D has an affect on the developing brain."

Schizophrenia is a poorly understood group of brain disorders that affect about 1 in a 100 Australians. It usually first presents in young adults. Symptoms include hearing voices and delusions.

(Source: University of Queensland: Archives of General Psychiatry)