Parents who have watched in horror as their young children stuff a handful of mud into their mouths while playing in the garden can relax.
For research suggests that eating mud or clay could actually be good for the stomach. Dining on dirt, or geophagy, is common among many cultures and has been reported in almost every country in the world. Now more than 480 cultural accounts of the practice — by missionaries, plantation doctors and explorers — have been analysed by researchers at Cornell University in New York.
While no one is suggesting that mud should be the new fad diet, the study, in The Quarterly Review of Biology, found the most plausible explanation for geophagy could be that earth acts as a shield against ingested parasites and plant toxins.
People may also crave dirt because it provides nutrients they lack such as iron, zinc, or calcium, the research found.