Farm exposures may protect against childhood allergic diseases such as asthma, hay fever and eczema but the effect on adults was unknown until recently.According to a study of 2,500 farming families and 1000 non farming families, farmers were less likely to have asthma symptoms, hay fever and eczema.
It did not really matter what specific type of farm work was done -- there was no significant differences between dairy, sheep and beef, and horticulture farmers.
The combined number of years of farm exposure in childhood and adulthood had a dose-dependent inverse association with symptoms.
Children living on a farm are at reduced risk of asthma (OR 0.68), hay fever (OR, 0.43), atopic dermatitis (OR, 0.80), and atopic sensitization (OR, 0.54) http://goo.gl/qVY2G
References:
Lifelong farm exposure may strongly reduce the risk of asthma in adults. J. Douwes, N. Travier, K. Huang, S. Cheng, J. McKenzie, G. Le Gros, E. von Mutius, N. Pearce (2007). Allergy 62 (10), 1158–1165. doi:10.1111/j.1398-9995.2007.01490.x
Children living on farms exposed to a wider range of microbes leading to lower asthma risk. NEJM, 2011.
Protective role of contact with livestock and farming lifestyle on asthma, in particular during childhood. ERJ January 1, 2012 vol. 39 no. 1 67-75.
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Einstein Coll of Med @EinsteinMed: Now you telll me! - RT @Allergy: How to reduce your risk of #asthma: spend whole life on a farm bit.ly/JMgiqM