Obesity is associated with a range of metabolic diseases and an elevated risk of cancer, so reducing weight can help to reduce many risks associated with excessive weight. However, for someone who is obese reducing weight does not necessarily lower the risk of all forms of cancer.
A new study, from the University of South Carolina, has looked onto colon and liver cancer. The study shows that the incidence of tumors in the colon remained unchanged after weight loss. This relates to studies using mice and this may not necessarily relate to humans.
For the research, scientists studied obese mice and obese mice that lost weight, and compared both sets with a control group. The obese and lean groups were exposed to a carcinogen and the research focused on whether losing weight provided protection to the rodents against the development of colon polyps or cancer.
The results indicated that losing weight did not protect the lean group. This suggests, according to the scientific research note, that “excess fat reduction did not protect mice from colon cancer progression and liver dysplastic lesion…even though these mice had improved blood glucose and leptin.”
Whether such a finding would relate to humans remains to be seen and will require further study. It is also important to point out that the study findings relate to a specific type of cancer.
The findings are published in the American Journal of Physiology – Gastrointestinal and Liver Physiology. The research paper is titled “Weight loss following diet-induced obesity does not alter colon tumorigenesis in the AOM mouse model.”
In related news on cancer, the U.S. Department of Health and Human Services 14th Report on Carcinogens has recently been issued. This includes seven newly reviewed substances and this brings the cumulative total to 248 listings of cancer causing substances. With this, the chemical trichloroethylene, and the metallic element cobalt and cobalt compounds plus well as five viruses that have been linked to cancer in humans, have each been added to the list.