And a Scandinavian study found that the older the cradle an infant sleeps in, the more dust and microorganisms it will contain, and the less likely it is that the child will eventually develop an allergy.
總而言之，人體內的兩種免疫反應需要經過適當的刺激以維持平衡，現代兒童因生活在過度保護的情境中，免疫刺激反而減少，使得過敏反應增高。