Could gum help the colon bounce back from surgery?
Whether surgery to lose weight can affect those risks is uncertain. Two earlier studies, one from the U.S. and the other from Sweden, found that the chances of obesity-related cancers decline after women have weight-loss surgery. But an earlier study from Lagergren’s group found the risks for breast and prostate cancers were unaffected by obesity surgery, and colorectal cancer risk increased. To investigate that finding further, Lagergren’s team collected 29 years’ worth of medical records on more than 77,000 people in Sweden who were diagnosed as obese between 1980 and 2009. About 15,000 of them underwent weight loss surgery. In the surgery group, 70 people developed colorectal cancer – a rate that was 60 percent greater than what would be expected for the larger Swedish population. When the researchers looked only at people who had surgery more than 10 years before the end of the study period, the number of cancer cases was 200 percent greater than the expected risk for the general population. In contrast, 373 people in the no-surgery group developed colorectal cancer, which was 26 percent more than would be expected in the population and that number remained stable over time. A two-fold increased risk for colorectal cancer is not a “negligible risk increase, but it should not be of any major concern for the individual patient since the absolute risk is still low,” Lagergren told Reuters Health in an email. In the U.S., for instance, 40 out of every 100,000 women and roughly 53 out of every 100,000 men develop colorectal cancer each year. Doubling that risk would make the annual figures 80 out of every 100,000 women and 106 out of every 100,000 men. Lagergren said that more studies are needed to confirm his results before they should be included in clinical decision-making about whether patients should undergo weight-loss surgery. The study results cannot prove that the surgery is the cause of the elevated cancer risk. And, Lagergren says it’s also not clear why the surgery might be tied to an elevated risk of colorectal cancer. One possibility is that dietary changes after surgery, and increasing protein in particular, could raise cancer risk, he speculated.
Past studies have hinted that gum might help cut that recovery time if the body responds to chewing by preparing the gut to receive food, researchers said. Although the new findings challenge that theory, one colorectal surgeon thinks gum is still worth a go. “It’s quite reasonable to try sugar-free gum to help stimulate gastrointestinal recovery after major abdominal surgery, as there appears to be no downside, and it’s cheap, unlike many other medications,” said Dr. Conor Delaney, from University Hospitals Case Medical Center in Cleveland. Delaney, who wasn’t involved in the new research, told Reuters Health that he and his own team have combined less-invasive surgery with a set recovery plan to cut hospital stays to two and a half days after so-called colorectal resection, on average. Their plan includes advising patients to chew gum after surgery. For the new study, Patrick Lim and colleagues from the University of Newcastle in New South Wales, Australia, randomly assigned people having either open or less-invasive colon surgery to chew gum four times a day after surgery or not to chew gum. Their study included 157 patients treated at one of two hospitals between 2008 and 2011. What the research team was looking for was how quickly patients regained their bowel function after surgery – measured by when they started producing gas. People who didn’t chew gum said it took an average of 51 hours – just over two days – for their intestines to start gearing up again, compared to 43 hours among gum chewers. However statistically, that difference could have been due to chance, according to Lim’s team. Delaney said it’s possible the new study simply didn’t include enough patients to tease out a clear difference between the groups. “There’s a lot of data suggesting that it’s probably about a 20-hour improvement” that comes with gum chewing, he added.