Abdominal fat may raise colon cancer risk

Adults who carry a lot fat around the middle may be at increased risk of colon cancer. Men and women with large waistlines are more likely to develop colon cancer than those who were trimmer around the middle. Waist size and waist-to-hip ratio, which are both indicators of abdominal obesity, appears to be more important in colon cancer risk than does overall weight. Body mass index (BMI) - a measure of weight in relation to height – is unrelated to colon cancer risk among women.Researchers from the German Institute of Human Nutrition in Potsdam-Rehbruecke, Europe, did a large study including 368,277 men and women who had their weight and body measurements taken and who completed questionnaires on diet, exercise and other lifestyle factors at the start of the study. Over six years, it was found that adults with larger midlines were more likely to develop colon cancer. Compared with the slimmest men, those with the largest waistlines were 39 percent more likely to be diagnosed with the cancer; women with the most fat around the middle had a 48-percent higher risk of the disease than those with the smallest  Journal of the National Cancer Institute,. BMI was linked to colon cancer risk among men only. Abdominal fat holds a particular influence over colon cancer risk. People with large waistlines often have a high amount of fat around the abdominal organs, and this type of fat is more metabolically active. It's possible that this visceral fat increases colon cancer risk by raising levels of certain hormones that affect cell growth, including the growth of cancer cells. Whatever the reason, the findings point to the importance of preventing abdominal obesity in particular. Previous studies have found the same sex difference when it comes to BMI and colon cancer risk. One reason may be the differences in body fat distribution between men and women. When a man has a high BMI, it's typically because of fat around the middle. Women, on the other hand, often carry much of their fat around the hips and thighs. So waist size may be a more accurate predictor of colon cancer risk than overall BMI, particularly for women. The study, therefore, shows that it's more important to keep an eye on the waist circumference, especially in women.