Obesity – Will It Become the Leading Cause of Preventable Cancer Among Women?

Obesity may have been the cause of over 124,000 cases of cancer diagnosed in Europe last year alone. In addition, obesity could become the leading preventable cause of cancer in women in Western countries within a decade.

The number of estimated cases was based on information from a number of sources, including the World Health Organization and the International Agency for Research on Cancer. Researchers calculated the proportion of body weight related cancers in 30 European countries. The researchers examined the cancer risk among men and women having a body mass index (BMI) score greater than 25. BMI is a ratio of weight to height used to determine if an individual is overweight or obese.

Statistics available from 2002 indicated that over 70,000 new cases out of a total of 2.2 million cancers could be attributed to being overweight or obese. By projecting these figures forward, an estimated 124,050 new cancers linked to body weight may have occurred in 2008, which would account for 3.2 percent of new cancers in men, and 8.6 percent in women. As the outbreak of obesity continues to spread, and with major cancer culprits such as smoking and hormone replacement therapy fading from the forefront, cancers linked to obesity could well become the leading preventable cause among women.

Study leader Dr Andrew Renehan, a cancer expert at the University of Manchester, said, “Obesity is catching up at a rate that makes it possible it could become the biggest attributable cause of cancer in women within the next decade.” The study findings were presented to a joint meeting of the European Cancer Organization and the European Society for Medical Oncology in Berlin.

Of all the cancers linked to obesity, colorectal cancer, breast cancer in menopausal women, and endometrial cancer accounted for 65 percent. In addition, some studies found obesity to be the cause of up to 20 percent of cancers in the United States, according to Renehan. The researchers also pointed out that the number of cases of obesity-related oesophageal cancers was especially high in the United Kingdom.

During the Berlin conference, Renehan stated, “I must emphasize that we are trying not to be sensationalist about this. These are very conservative estimates, and it’s quite likely that the numbers are, in fact, higher.” He also pointed out, “This country accounts for 54 percent of new cases across all 30 countries.” Renehan went on to explain, “This may be due to synergistic interactions between smoking, alcohol, excess body weight and acid reflux—and is currently an area where research is required.”

Although it remains unclear as to why being overweight increases the risk of cancer, hormones such as estrogen that promote tumor growth are highly suspect. Another contributing factor may be that individuals having large bellies also have a higher stomach acid content that may promote stomach, intestinal or esophageal cancer.

Renehan said that because simply telling people to lose weight for their health has not worked, new strategies must be found to help people stay slim. He says, “We need to find the biological mechanism to help people find other ways of tackling obesity.”

In an interview, Renehan noted, “We are now shifting our emphasis to people who already have cancer.” The researchers are working to determine whether obesity increases the likelihood of current cancer patients developing a second type of tumor, or if being overweight causes a decreased response to chemotherapy.