The study was performed in collaboration with Linköping University, which is conducting a population study called ABIS (All Babies in Southeast Sweden).

"This is the first study to show a link between vegetable intake during pregnancy and the risk of the child subsequently developing Type 1 diabetes, but more studies of various kinds will be needed before we can say anything definitive," says researcher and clinical nutritionist Hilde Brekke from the Sahlgrenska Academy. Blood samples from almost 6,000 five year-olds were analysed in the study.

In Type 1 diabetes, certain cells in the pancreas gradually get worse at producing insulin, leading to insulin deficiency. Children at risk of developing Type 1 diabetes have antibodies in their blood which attack these insulin-producing cells. Of the 6,000 children tested, 3% had either elevated levels of these antibodies or fully developed Type 1 diabetes at the age of five. These risk markers were up to twice as common in children whose mothers rarely ate vegetables during pregnancy. The risk was lowest among children whose mothers stated that they ate vegetables every day.

"We cannot say with certainty on the basis of this study that it's the vegetables themselves that have this protective effect, but other factors related to vegetable intake, such as the mother's standard of education, do not seem to explain the link," says Brekke. "Nor can this protection be explained by other measured dietary factors or other known risk factors."

The term "Vegetables "in this study included all vegetables except for root vegetables.