Babies born during famine are at higher risk of schizophrenia

A new study has found that malnutrition can harm mental as well as physical health, and babies born during famine are at higher risk of schizophrenia.

According to Shanghai researchers the Chinese famine of 1959-1961 increased the risk of schizophrenia in later life from 0.84% to 2.15%.

However it is unclear at present whether it is lack of food in general or a lack of specific nutrients while in the womb that is most important.

The study findings support those of a previous study in Holland where schizophrenia risk was doubled among children conceived during war-related food shortages in 1944-1945.

In Holland, people ate tulip bulbs during the famine.

In the China study, the team from the Shanghai Jiao Tong University compared the rates of schizophrenia among those born before, during and after the famine years in the Wuhu region, which currently has a population of 62 million.

During the famine, the birth rate for the area decreased by around 80%, but it was found that among the babies that were born, more went on to develop schizophrenia as adults than the babies born during non-famine years.

The schizophrenia risk increased from 0.84% in 1959 to 2.15% in 1960 and 1.81% in 1961.

The researchers say that based on the trends found, they believe the critical time of famine is during the first three months of pregnancy.

According to Dr David St Clair and his team, there are many possible explanations for this; it might be that lack of food adversely affected the developing embryo's brain, thereby increasing the risk of schizophrenia; or it might be that certain essential nutrients were missing from the pregnant women's diets, causing harm to the baby, in a similar to the way that folic acid deficiency can lead to neural tube defects in unborn children.

Yet another possibility is that during the famine the mothers ate more food substitutes that could have been toxic to the baby, in China for example the women ate tree bark and green algae grown at home in vats of urine.

Some researchers have already shown a link between folic acid and schizophrenia.

The researchers say it is also possible that women carrying genes for schizophrenia were more likely to conceive and have successful pregnancies than other women, at a time when the birth rate was going down due to famine, and schizophrenia genes might confer some survival benefit.

There was however no difference seen in the number of family members with schizophrenia among the babies who went on to develop schizophrenia before, during and after the famine, suggesting this was not the most likely cause of the trend.

Dr Richard Neugebauer from the New York State Psychiatric Institute in the U.S. says the study findings raise the possibility of public health interventions to prevent schizophrenia.

He says, depending on the cause, better nutrition or supplements of specific micronutrients such as folic acid might help.

Paul Corry from the mental health charity Rethink says good nutrition is central to good physical and mental health, and some foods can contribute to cause illness while the absence of certain minerals and vitamins and the addition of additives can both cause mental illness and hinder recovery.

Corry says there is strong evidence that low folic acid is associated with depression and schizophrenia.

The study is published in the JAMA: The Journal of the American Medical Association.