Rugby and meat: a treat for the gut? A study suggests yes. Here Tony Woodcock (left) and Owen Franks of the All Blacks rugby team turn sausages on the barbecue in 2011 in Christchurch, New Zealand. Phil Walter/Getty Images hide caption

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Even some euro bank notes may need a good scrubbing. Like dollar bills, these notes are made from cotton and they harbor an array of bacteria. Thomas Leuthard/The Preiser Project/Flickr hide caption

itoggle caption Thomas Leuthard/The Preiser Project/Flickr

A probiotic commonly found in yogurt seems to help women lose more weight and fat, a recent study finds. But you still have to eat healthy to see an effect. iStockphoto hide caption

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You tried burping. You tried bouncing. You tried swaddling. Now what? iStockphoto hide caption

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The interior of the nose is like a lush rain forest that's barely been explored. Courtesy of Sunje Pamp hide caption

itoggle caption Courtesy of Sunje Pamp

A sweet way to avoid the dentist? Microbiologists are developing a probiotic mint that uses dead bacteria to fight off cavities. Morgan Walker/NPR hide caption

itoggle caption Morgan Walker/NPR

Microbiologist Christina Agapakis (left) and artist Sissel Tolass show off the cheese they made with bacteria from human skin. The project was part of Agapakis' graduate thesis at Harvard Medical School. Courtesy of Grow Your Own ... Life After Nature at Science Gallery at Trinity College Dublin hide caption

itoggle caption Courtesy of Grow Your Own ... Life After Nature at Science Gallery at Trinity College Dublin

He's not just getting a cold. He's building his microbiome. iStockphoto.com hide caption

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