• Hygiene
• Thumb-sucking

The hygiene hypothesis has come under fire in recent years as being too simplistic to explain the rise in allergic disease, but two fascinating studies suggest that it is alive and well.

Children frequently stick their mucky fingers and thumbs in their mouths and in doing so expose themselves to organisms that might induce an immunological response. Researchers from Dunedin, New Zealand, sought to investigate whether those who do this more are protected from allergic disease (Lynch S et al. Pediatrics 2016. doi:10.1542/peds.2016-0443). Over 1000 children born in the 1970s joined a …