Here's something for you to chew on...

By gum, it might be good for you Recent studies show that gum chewing may speed recovery from bowel surgery. Chewing gum — banned in schools and Singapore, discouraged by dentists, deplored as bad etiquette — is proving to have some unlikely health benefits. Let’s start with your teeth. Chewing gum generates extra saliva, which may help wash away the Streptococcus mutans bacteria that are the main cause of cavities. Trident and some other sugarless brands are sweetened with xylitol, which is chemically related to sugar and just as sweet, but apparently doesn’t “feed” cavity-causing bacteria the way regular sugar does. Sorbitol, a sugar alcohol like xylitol, is also used to sweeten sugarless gums, but a review published in 2006 concluded that xylitol is the better cavity fighter. Heartburn is often caused by gastroesophageal reflux (GERD), which occurs when some faulty digestive-system plumbing allows stomach contents to back up into the esophagus. In 2005, British researchers reported the results of a study of 30 GERD sufferers who chewed gum for about half an hour after they ate. Measurements showed that the gum lowered acid levels in their esophagi. The researchers speculated that frequent swallowing helped control reflux and push any errant stomach contents back where they belong. Students are always looking for an edge; jawing gum might be a safe way to get it. Several years ago, Dr. Kenneth Allen, a professor at New York University’s College of Dentistry, had students learning dental anatomy either chew sugarless gum or study gum-free. When they were tested on the material, the chewers scored higher than the non-chewers. Gum gets the bowels going After abdominal surgery, your bowels tend to shut down. All sorts of misery may ensue, including a painful, bloated feeling, vomiting, and dehydration. Severe cases lead to longer hospital stays and all the health risks they entail. Traditionally, patients haven’t been allowed to eat after abdominal surgery until there’s some evidence that their bowels are moving again. For this reason, doctors and patients alike rejoice at the first postoperative episode of flatus. But now there is some evidence that waiting may be counterproductive and that small quantities of food soon after surgery may hasten the return of normal bowel function. Yet some recovering digestive systems can’t handle even those tiny amounts. Gum-chewing for abdominal surgery patients has been proposed as a form of “sham feeding” that could get the bowels moving again without actually putting food or fluid through them. Chewing stimulates the vagus nerve, a long nerve that originates in the head but has many branches, including some that control the bowels. The vagus nerve may also play a role in the release of gastrointestinal hormones that stimulate bowel activity. Get a move on Chewing may activate the bowels via the vagus nerve, which extends from the head to the abdomen. Several years ago, researchers at Gunma University School of Medicine in Japan reported that gum-chewing speeded recovery from laparoscopic colectomy. In 2006, the same group reported that chewing gum accelerated the recovery of patients who had surgery for colon cancer. Doctors at Santa Barbara Cottage Hospital in California reported similar results in the February 2006 issue of the Archives of Surgery. Their study involved 34 patients who had colon surgery for diverticulitis, an inflammatory condition, or cancer. Important firsts — flatus, bowel movement, feelings of hunger — all happened sooner for the 17 patients randomized to postoperative gum-chewing. They also spent fewer days in the hospital (4.3 versus 6.8). The doctors did the math and concluded that gum-shortened hospital stays after colectomies could save $118.9 million, less the $47,531 cost of the gum. The results haven’t been unanimous. A month before the Californians reported their findings, doctors at a hospital in Wales reported negative results from a similar study. The Wm. Wrigley Jr. Company, which has already paid for some of this research, announced in March that it was establishing a science institute to fund studies into gum-chewing as a way to lose weight, relieve stress, and increase concentration. If chewing gum does all that (and doubles your pleasure and fun) then Wrigley may have found a whole new medicinal market for its products, and Singapore may have to rethink its antigum policies. The country relaxed its laws to allow chewing for therapeutic purposes, of which there may be plenty. All rights reserved.Harvard Health Letterwww.health.harvard.edu/healthVolume 31 - Number 10 - August 2006