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the reason for the increased risk for colon cancer? Some researchers believe
so. But if things like insulin or diets are responsible for the relationship
between colon cancer and obesity, why wouldn’t colon cancer appear at
equal rates among obese men and women? Researchers have a theory about
this too.
Some researchers theorize that, as with breast cancer, estrogen may be
playing a role in colon-cancer rates in obese women. However, in the case of
colon cancer, estrogen may actually be having an opposite effect. It may actu-
ally protect against colon-cancer development whereas it spurs breast-cancer
development. As we already learned, excess fat later in life translates into
more estrogen. So, while this increased estrogen greatly increases a woman’s
risk of developing breast cancer, it seems to reduce her risk of developing
colon cancer. In the end, estrogen may be responsible for the differences in
colon cancer rates in men and women.
Esophageal
Cancer
According to the NCI, overweight and obese people
are twice as likely as healthy-weight people to
develop esophageal cancer (cancer of the esophagus).