We urgently need better evidence about how our experiences before birth might influence our long-term health. Most research in this area has focused on the diets and lifestyles of pregnant mothers, but the evidence is patchy and health advice offered to pregnant women can be confusing and inconsistent. More recent research suggests that a father's diet and behaviour can influence the health of his unborn children, but very little public health advice is currently offered to fathers-to-be.

Some studies have found that children born to mothers who adhere to a Mediterranean diet (typified by a high intake of vegetables, legumes, fruits and nuts, unrefined cereals, fish and olive oil) during pregnancy have better health than their peers. But does this represent a causal effect of Mediterranean diet on offspring health or is it merely correlated due to confounding factors? And what about fathers? Can their adherence to a Mediterranean diet affect their child’s health?