Objective: To discuss current evidence about the relation between prenatal and childhood Mediterranean diet, and the development of asthma and allergies in children.
Design: Review of the literature.
Setting and results: Four recent studies conducted in Mediterranean countries (Spain, Greece) and one conducted in Mexico evaluated the association between childhood Mediterranean diet and asthma outcomes in children. All of the studies reported beneficial associations between a high level of adherence to the Mediterranean diet during childhood and symptoms of asthma or allergic rhinitis. Individual foods or food groups contributing to the protective effect of Mediterranean diet included fish, fruits, vegetables, legumes, nuts and cereals, while detrimental components included red meat, margarine and junk food intake. Two studies focused on prenatal Mediterranean diet: the first is a birth cohort in Spain that showed a protective effect of a high adherence to the Mediterranean diet during pregnancy on persistent wheeze, atopic wheeze and atopy at the age of 6.5 years; while the second is a cross-sectional study in Mexico, collecting information more than 6 years after pregnancy, that showed no associations between maternal Mediterranean diet during pregnancy and allergic symptoms in childhood except for current sneezing.
Conclusions: Findings from recent studies suggest that a high level of adherence to the Mediterranean diet early in life protects against the development of asthma and atopy in children. Further studies are needed to better understand the mechanisms of this protective effect, to evaluate the most relevant window of exposure, and to address specific components of diet in relation to disease.