Inverse association of farm milk consumption with asthma and allergy in rural and suburban populations across Europe.
BACKGROUND
Dietary interventions as a means for atopy prevention attract great interest. Some studies in rural environments claimed an inverse association between consumption of farm-produced dairy products and the prevalence of allergic diseases, but current evidence is controversial.


OBJECTIVE
To investigate whether consumption of farm-produced products is associated with a lower prevalence of asthma and allergy when compared with shop-purchased products.


METHODS
Cross sectional multi-centre study (PARSIFAL) including 14,893 children aged 5-13 years from five European countries (2823 from farm families and 4606 attending Steiner Schools as well as 5440 farm reference and 2024 Steiner reference children). A detailed questionnaire including a dietary component was completed and allergen-specific IgE was measured in serum.


RESULTS
Farm milk consumption ever in life showed a statistically significant inverse association with asthma: covariate adjusted odds ratio (aOR) 0.74 [95% confidence interval (CI) 0.61-0.88], rhinoconjunctivitis: aOR 0.56 (0.43-0.73) and sensitization to pollen and the food mix fx5 (cut-off level of >or=3.5 kU/L): aOR 0.67 (0.47-0.96) and aOR 0.42 (0.19-0.92), respectively, and sensitization to horse dander: aOR 0.50 (95% CI 0.28-0.87). The associations were observed in all four subpopulations and independent of farm-related co-exposures. Other farm-produced products were not independently related to any allergy-related health outcome.


CONCLUSIONS
Our results indicate that consumption of farm milk may offer protection against asthma and allergy. A deepened understanding of the relevant protective components of farm milk and a better insight into the biological mechanisms underlying this association are warranted as a basis for the development of a safe product for prevention.
Waser
M
M
Institute of Social and Preventive Medicine, University of Basel, Switzerland. Marco.Waser@unibas.ch
Michels
K B
KB
Bieli
C
C
Flöistrup
H
H
Pershagen
G
G
von Mutius
E
E
Ege
M
M
Riedler
J
J
Schram-Bijkerk
D
D
Brunekreef
B
B
van Hage
M
M
Lauener
R
R
Braun-Fahrländer
C
C
D000293:Adolescent; D000383:Agriculture; D000485:Allergens / Q000276:immunology; D000818:Animals; D001249:Asthma / Q000453:epidemiology / Q000517:prevention & control*; D002417:Cattle; D002648:Child; D002664:Child Nutritional Physiological Phenomena; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D003611:Dairy Products; D005060:Europe / Q000453:epidemiology; D006801:Humans; D006967:Hypersensitivity / Q000453:epidemiology / Q000517:prevention & control*; D007073:Immunoglobulin E / Q000097:blood; D008892:Milk; D015995:Prevalence; D012423:Rural Health; D018881:Suburban Health
D000485:Allergens; D007073:Immunoglobulin E