A review of research from the Center for Chemical Regulation and Food Safety finds that the quantity of food consumed by pregnant women for increasing a baby’s birth weight is less important than what types of foods she eats. After systematically analyzing 11 relevant studies, the researchers found that higher birth weights—associated with better brain development during later years—are linked with the amount of fruits and vegetables a mother eats during pregnancy.

Using seven studies, researchers found that low vegetable consumption during pregnancy resulted in more than three times the risk of giving birth to a child with low gestational weight. Other studies found a correlation between higher fruit consumption by expectant mothers and a higher birth weight of babies. Much of the research showing these relationships occurred in developed countries where a conventional Western diet is prevalent.