A new analysis conducted by The George Institute for International Health in Sydney, Australia, has shown a clear link between obesity and colorectal cancer.
According to the report, obese individuals have a 20 percent greater risk of developing colorectal cancer compared to those of normal weight.
The results also indicated that obese men are at 30 percent greater risk of developing the cancer compared with obese women.
It showed that carrying even a few excess kilos substantially increases the risk of colorectal cancer; for every 5 kg weight gain the risk of developing the cancer increases by 7 percent.
Dr Rachel Huxley and colleagues reviewed over 70,000 patients in an analysis that included studies all across the globe.
The new report carries links with the latest report from the World Cancer Research Fund Report, which provides further support regarding the link between obesity and cancer.
Importantly, the primary recommendation of the report is; "Be as lean as possible within the normal range of body weight", supported by a public health goal of 'Median adult body mass index (BMI) to be between 21 and 23'. All eight recommendations made in the report were focused on healthy eating, drinking and physical activity, creating a sincere message of the relationship between diet and cancer risk.
"Although the mechanisms that explain the link between excess weight and cancer remain to be elucidated, substantial evidence supports an important role for diet and physical activity," Dr Huxley added.
Both the international and George Institute report stress the increasing levels of obesity in both high income and developing countries.
The researchers concluded by stating, while 20 percent is a considerable risk, previous reviews have suggested that obesity may be associated with up to 30 - 60 percent greater risk of colorectal cancer.
However, Dr Huxley said: "This over-estimation is most likely due to the impact of publication bias in medical and scientific journals. Regardless, a 20 percent greater risk is still considerable and sends a clear message about watching what you eat and being more physically active."
The report is published in the journal Cancer Epidemiology, Biomarkers and Prevention.