'Fat Hormone' Tied to Higher Colon Cancer Risk
More precancerous polyps seen in small study as body fat increased
By Alan Mozes
THURSDAY, Feb. 20, 2014 (HealthDay News) -- Obesity seems to increase the likelihood for developing precancerous growths called colorectal polyps, according to new research that offers fresh insight into colon cancer risk.
Specifically, the study links polyp risk to several key characteristics of obesity, including having elevated levels of the fat hormone leptin, having a higher body mass index (BMI) and having a larger waistline. BMI is a measurement of body fat taking height and weight into account.
However, investigators stressed that the current findings are not, as yet, definitive, and should not lead to any immediate revisions of current colorectal screening recommendations.
Co-author Jenifer Fenton said the study "cannot assume any cause, only association." Fenton is an assistant professor and researcher in the department of food science and human nutrition at Michigan State University, in East Lansing.
"In order to change the recommendations, which right now advise men to get screened starting at the age of 50, we'd have to find out if obese men are more likely to develop these polyps at an earlier age than their lean counterparts," Fenton explained.
"But we can't yet say that," she said. "For the moment, all we can say for sure is that obese men in this particular population were more likely to have polyps. We will need larger studies following a more generalized population over time to learn about timing."
The study, funded in part by the U.S. National Cancer Institute, was published recently in the journal PLoS One.
To explore a potential link between obesity and colon cancer risk, between mid-2009 and early 2011 the authors focused on 126 seemingly healthy men aged 48 to 65, all of whom were Michigan residents.
All the men underwent colonoscopies. In addition, the team noted BMI scores, waist measurements and leptin levels for all participants.
Roughly four in 10 of the men were found to be obese (with a BMI of 30 and up), with 78 percent falling into the category of either obese or overweight.
And when focusing on the overweight/obese group, the team found that 30 percent had more than one polyp.