Little kids often put things into their mouths that don't belong there, from coins and jewelry to small toys and batteries. Even though grownups know better, they sometimes accidentally swallow items they shouldn't either -- and these objects may get stuck in their throats or lodged in their digestive tracts.

A review study from Germany, published in the journal Deutsches Arzteblatt International, recently identified the three items most likely to be inadvertently swallowed by adults. First on the list was fish bones followed by chicken bones, neither of which seem that unusual. The third most common item was dentures, which may loosen up in an older person's mouth while eating. 

Although the researchers didn't speculate beyond these three items, I asked Dr. Ram Chuttani, a gastroenterologist and director of endoscopy at Beth Israel Deaconess Medical Center in Boston to do so. He was not involved in the study, but described some of the most frequent objects he's known to unintentionally slide down an adult's throat during his medical career.

"Coins are a big one," says Chuttani. "How they get there is difficult to say, but they're not uncommon." Toothpicks are also common, he suggests, and they're one of the more dangerous because they are long, thin, pointy, and wooden.

Wooden objects, such as pencils and toothpicks, are not easily picked up on X-rays, Chuttani explains. Also tough to see are broken pieces of glass whose sharp edges can damage your insides. So can swallowing an open safety pin, and Chuttani says that sometimes prisoners purposely swallow sharp items like razor blades because they know it will temporarily get them out of jail and into the hospital.

The German study also recommends seeking prompt medical attention if items such as batteries and magnets are accidentally swallowed. A battery stuck in the esophagus needs to be removed immediately because it might leak alkaline substances. It can also put pressure on the wall of esophagus, or generate electrical currents that can short-circuit its function. Batteries that make their way into the stomach might corrode the lining there.

Magnets can be especially risky when you swallow more than one of them, points out Chuttani. He says that if one magnet winds up in the stomach while another is in the small intestine, they can attract each other causing the walls of the intestine to get trapped in between. Pressure can build up and puncture a hole in the intestine.

Sometimes people do dumb things and an object glides down their gullet -- whole. Chuttani once removed a ping pong ball that a drunk college student chugged during a memorable game of beer pong. He's also retrieved a latex glove that a psych patient stuck down his throat, and has drudged up swallowed condoms.

The study shows pictures taken after folks accidentally swallowed a toothbrush, spoon, or dental drill bit, while other case reports have described women who have mistakenly sent a butter knife or pen down their throats.

Chuttani says most of the time these foreign objects pass by themselves.

According to the study, about 80 percent of the time an item winds its way through the curvy GI tract without causing any trouble. It typically comes out in your poop within 4 to 6 days. In rare instances, an object may take up to 4 weeks to pass through a person's body safely.

Roughly 20 percent of cases need endoscopy, in which doctors look inside the body, locate the item, and then gently remove it. 

A very small minority -- less than 1 percent of cases -- require surgery to retrieve the object.

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