Serrated polyps (such as adenomas) are associated with an increased risk of colorectal cancer. However, a Norwegian study now confirms that they are not dangerous in themselves and do not cause disease. The study was published in “BMJ Gut”. Researchers at Oslo University Hospital included 12,955 people (aged 50 to 64 years) in the study using flexible sigmoidoscopy; the control group consisted of 78,220 people. 103 study subjects had large serrated polyps, 81 of whom were included in the analysis. 1,488 had non-advanced adenomas and 701 had advanced adenomas. The mean follow-up time was 10.9 years. Compared to controls, the cancer risk was 2.5 times higher in those with serrated polyps, twice as high in those with advanced adenomas, and 60% higher in those with non-advanced adenomas. Large serrated polyps are an independent risk factor for cancer. Of these types of polyps, 23 were not removed, and none of them developed malignancy.