污垢对你有好处:比如,生活在农场中的孩子患上过敏和哮喘的几率要比城市儿童小。不过,一项日前发表于《科学》杂志的研究表明,友好微生物的保护效应似乎同样依赖于一个人的基因组成。将儿童过敏和哮喘增加归咎于缺少对污垢和微生物的接触——这种观点被称为“卫生假说”。关于潜在的机制,有证据表明,一种名为内毒素的细菌蛋白对遏制过度活跃的免疫系统发挥着重要作用。内毒素能在诸如大肠杆菌等很多常见细菌种 Dirt is good for you: For example, children living in farms are less likely to have allergies and asthma than urban children. However, a study published recently in Science shows that the protective effect of friendly microbes seems to depend equally on a person’s genetic makeup. Attributing increased allergies and asthma in children to the lack of exposure to foulants and microbes - a concept known as the “health hypothesis.” With regard to the underlying mechanisms, there is evidence that a bacterial protein called endotoxin plays an important role in containing an overly active immune system. Endotoxins can be found in many common bacterial species such as E. coli