Swiss Tropical and Public Health Institute, Basel, Switzerland.
J Allergy Clin Immunol. 2011 Oct;128(4):766-773.e4. doi: 10.1016/j.jaci.2011.07.048. Epub 2011 Aug 27.
Farm milk consumption has been identified as an exposure that might contribute to the protective effect of farm life on childhood asthma and allergies. The mechanism of action and the role of particular constituents of farm milk, however, are not yet clear.
We sought to investigate the farm milk effect and determine responsible milk constituents.
In rural regions of Germany, Austria, and Switzerland, a comprehensive questionnaire about farm milk consumption and other farm-related exposures was completed by parents of 8334 school-aged children, and 7606 of them provided serum samples to assess specific IgE levels. In 800 cow's milk samples collected at the participants' homes, viable bacterial counts, whey protein levels, and total fat content were analyzed. Asthma, atopy, and hay fever were associated to reported milk consumption and for the first time to objectively measured milk constituents by using multiple regression analyses.
Reported raw milk consumption was inversely associated to asthma (adjusted odds ratio [aOR], 0.59; 95% CI, 0.46-0.74), atopy (aOR, 0.74; 95% CI, 0.61-0.90), and hay fever (aOR, 0.51; 95% CI, 0.37-0.69) independent of other farm exposures. Boiled farm milk did not show a protective effect. Total viable bacterial counts and total fat content of milk were not significantly related to asthma or atopy. Increased levels of the whey proteins BSA (aOR for highest vs lowest levels and asthma, 0.53; 95% CI, 0.30-0.97), α-lactalbumin (aOR for interquartile range and asthma, 0.71; 95% CI, 0.52-0.97), and β-lactoglobulin (aOR for interquartile range and asthma, 0.62; 95% CI, 0.39-0.97), however, were inversely associated with asthma but not with atopy.
The findings suggest that the protective effect of raw milk consumption on asthma might be associated with the whey protein fraction of milk.
农场牛奶的消费已被确定为可能有助于农场生活对儿童哮喘和过敏产生保护作用的一种暴露因素。然而，其作用机制和农场牛奶中特定成分的作用尚不清楚。
我们旨在研究农场牛奶的作用并确定其相关的牛奶成分。
在德国、奥地利和瑞士的农村地区，由 8334 名学龄儿童的父母完成了一份关于农场牛奶消费和其他与农场相关的暴露情况的综合问卷，其中 7606 名儿童提供了血清样本以评估特定 IgE 水平。在家中收集的 800 份牛奶样本中，分析了活菌计数、乳清蛋白水平和总脂肪含量。通过多元回归分析，将报告的牛奶摄入量与哮喘、过敏和花粉热联系起来，并首次将其与客观测量的牛奶成分联系起来。
报告的生牛奶消费与哮喘（调整后的比值比 [aOR]，0.59；95%CI，0.46-0.74）、过敏（aOR，0.74；95%CI，0.61-0.90）和花粉热（aOR，0.51；95%CI，0.37-0.69）呈负相关，且独立于其他农场暴露因素。煮沸的农场牛奶没有表现出保护作用。牛奶的总活菌计数和总脂肪含量与哮喘或过敏无显著相关性。乳清蛋白 BSA（最高与最低水平与哮喘的比值比 [aOR]，0.53；95%CI，0.30-0.97）、α-乳白蛋白（四分位间距与哮喘的比值比 [aOR]，0.71；95%CI，0.52-0.97）和β-乳球蛋白（四分位间距与哮喘的比值比 [aOR]，0.62；95%CI，0.39-0.97）水平升高与哮喘呈负相关，但与过敏无关。
这些发现表明，生牛奶消费对哮喘的保护作用可能与牛奶的乳清蛋白部分有关。
