Farming in childhood, diet in adulthood and asthma history

The decrease in the number of children living on traditional farms in France during early childhood and changes in diet could both play a role in the increase of asthma prevalence over the last decades. This article aims to assess i) the association of farming lifestyle in childhood and asthma ii) whether diet in adulthood modifies the association between farming lifestyle in childhood and adult-onset asthma. In the French E3N study (54,018 females, 43-68 years), three indicators of farming lifestyle were defined: one using individual data (having farmer parents), and two using ecological data (born in a rural area, exposure to cattle). All farming lifestyle indicators were related with childhood- (<16 years), and adult-onset asthma: OR (95% CI) for farmer parents were 0.54 (0.42-0.70), 0.72 (0.62-0.84) respectively, and with diet in adulthood, in particular with a high fruit and a low wine intakes. The association between farmer parents and adult-onset asthma was not modified by diet in adulthood. Results extend previous observations in younger cohorts on the protective role of contact with livestock and farming lifestyle on asthma, in particular during childhood