Study helps confirm what is becoming more clear to researchers
Kimmie Ng, MD, MPH, a professor at Harvard Medical School and oncologist at Dana-Farber Cancer Institute, both in Boston, said in an interview that the study helps confirm what is becoming more clear to researchers.
Dr. Kimmie Ng
“We do think that exposures over the life course are the ones that will be most strongly contributing to a risk of colorectal cancer as an adult,” she said. “With obesity, what we think is happening is that it’s setting up this milieu of chronic inflammation and insulin resistance and we know those two factors can lead to higher rates of colorectal cancer development and increased tumor growth.”
She said the ideal, but impractical, way to do the study would be to follow healthy people from childhood and document their weight over a lifetime. In this case-control study, people were asked to recall their weight at different time periods, which is a limitation and could lead to recall bias.
But the study is important, Dr. Ng said, and it adds convincing evidence that addressing the link between excess weight and CRC and chronic diseases should be a public health priority. “With the recent rise in young-onset colorectal cancer since the 1990s there has been a lot of interest in looking at whether obesity is a major contributor to that rising trend,” Dr. Ng noted. “If obesity is truly linked to colorectal cancer, these rising rates of obesity are very worrisome for potentially leading to more colorectal cancers in young adulthood and beyond.“
The study authors and Dr. Ng report no relevant financial relationships.
The new research was funded by the German Research Council, the Interdisciplinary Research Program of the National Center for Tumor Diseases, Germany, and the German Federal Ministry of Education and Research.