Role of diet in the development of immune tolerance in the context of allergic disease

Purpose of review Diet is arguably one of the most significant environmental exposures during early development. Here, we explore the effects of key perinatal dietary exposures on immune development and susceptibility to allergic disease. Recent findings Dietary changes are at the centre of the emerging epigenetic paradigms that underpin the rise in many modern diseases. There is growing evidence that exposures in pregnancy and the early postnatal period can modify gene expression and disease susceptibility. Specific nutrients, including antioxidants, oligosaccharides, polyunsaturated fatty acids, folate and other vitamins, have documented effects on immune function. Some have also been implicated in modified risk of allergic disease in observational studies. Intervention studies are largely limited to trials with polyunsaturated fatty acids and oligosaccharides, showing preliminary but yet unconfirmed benefits in allergy prevention. Avoidance of food allergens in pregnancy, lactation or infancy has provided no clear evidence in allergy prevention and is no longer recommended. Rather there is focus on their role in tolerance induction. Summary Modern dietary changes are clearly implicated in the rising propensity for inflammatory immune responses. These dietary changes, which appear to be providing less tolerogenic conditions during early immune programming, may provide important avenues for preventing disease.