Colon cancer risks linked to obesity says research
Large waist measurements and waist-to-hip ratios are linked to increased risks of colon cancer in both men and women, German researchers have claimed.
The scientists added that a high body mass index (BMI) increased colon cancer risks by much more in men than in women.
The study by the German Institute of Human Nutrition Potsdam-Rehbr found no link between weight and rectal cancer.
"Our results support the hypothesis that abdominal body fat is especially important for development of colon cancer," said Heiner Boeing of the European Prospective Investigation into Cancer and Nutrition (EPIC), which supplied the data for the study.
"This agrees with our observation that BMI is rather inappropriate for predicting colon cancer in women because the relation between BMI and waist circumference is not as close as in men.
"This is probably because men gain weight primarily by increasing abdominal body fat, whereas in women, body fat normally also accumulates in other parts of the body."
The researchers said that the cause of the relationship remained unclear, but speculated that it may be related to the levels of insulin circulating in the body.
Abdominal obesity has been linked with increased insulin resistance. Hormonal factors are also currently being considered, said scientists.
Ed Yong, health information officer at Cancer Research UK, said: "This study highlights the importance of maintaining a healthy weight to reduce your risk of cancer.
"As well as colon cancer, the EPIC study has also shown that being overweight or obese can increase the risk of breast cancer after menopause, as well as kidney and foodpipe cancers.
"These findings are especially important given the rising rates of adult and childhood obesity in the UK."
The study was published in the Journal of the National Cancer Institute.
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