A prospective, randomized trial concluded that the early introduction of peanuts significantly decreased the frequency of the development of peanut allergy among children at high risk for this allergy. The study randomized 640 infants with severe eczema, egg allergy, or both to consume or avoid peanuts until 60 months of age. Participants (4-11 months of age at randomization) were assigned to separate study cohorts on the basis of preexisting sensitivity to peanut extract determined with the use of a skin-prick test. Among the 530 infants who initially had negative results on the skin-prick test, the prevalence of peanut allergy at 60 months of age was 13.7% in the avoidance group and 1.9% in the consumption group (P<0.001). Among the 98 participants who initially had positive test results, the prevalence of peanut allergy was 35.3% in the avoidance group and 10.6% in the consumption group (P=0.004). There was no significant between-group difference in the incidence of serious adverse events. Thus, early consumption was effective not only in high-risk infants who showed no indication of peanut sensitivity at study entry (primary prevention) but also in infants who had slight peanut sensitivity (secondary prevention). Observational studies showed that earlier introduction of egg and milk into an infant’s diet was also associated with a decrease in the development of allergy. Source: http://www.nejm.org/一项前瞻性随机试验得出的结论是早期食用花生显著降低对花生过敏高风险儿童的过敏发生率。该研究把640名患严重湿疹和/或鸡蛋过敏的婴儿随机分为食用或避免花生两组直到60个月年龄。根据对花生提取物皮试结果所测定的既有花生过敏与否把参与者（随机分组时年龄4-11个月）分别分组。其中530名最初皮试阴性的婴儿，在60个月时花生过敏的患病率避免组和食用组分别为13.7％和1.9％（P <0.001）。其中98名最初皮试阳性的婴儿，在60个月时花生过敏的患病率避免组和食用组分别为35.3％和10.6％（P = 0.004）。严重不良事件的发生率没有显著的组间差异。因此，早期食用花生不仅对在研究开始时无花生过敏迹象的高风险婴儿有效（一级预防），而且对轻度花生过敏的婴儿也有效（二级预防）。有观察性研究表明，在婴儿饮食中较早地引入鸡蛋和牛奶也与过敏发生的减少有关。来源：http://www.nejm.org/
