By Jimmy Downs

A study reported early today on foodconsumer.org found that people who had cancer are less likely to have Alzheimer’s disease and people who have Alzheimer’s less likely to acquire cancer.

Some scientists speculated that reproductive hormones are a likely link between cancer and Alzheimer’s disease.  Those who are familiar with the research on Alzheimer’s and cancer may not be surprised to hear of this link.

The study was led by Catherine M. Roe of Washington University School of Medicine in St. Louis and colleagues and published in Neurology.

Previous studies have linked lower testosterone levels to high risk of Alzheimer’s disease.  Women generally have a high risk of Alzheimer’s because they have lower levels of the male hormone compared to males.

On the other hand, high levels of this male hormone have been associated with high risk of prostate cancer among other things.

Other hormones are more than likely to play a role as well in the link between Alzheimer’s disease and cancer.

One hormone known as leptin produced by fat cells that at high levels was associated with reduced risk of developing Alzheimer’s disease and dementia, according to a recent US study published in the Journal of American Medical Association.

For the study, researchers of Boston University Medical Center examined data collected during a 12 year follow-up from 2000 volunteers. They found about 25 percent of the participants who had the lowest levels of leptin developed Alzheimer’s disease compared to six percent in those who had highest levels.

Now leptin has already been linked to cancer, at least colon cancer.  A study led by researchers from the University of California, San Diego School of Medicine and published Jan 15, 2005 in BJS suggests that high levels of the fat hormone may boost the growth of colon cancer.

Leptin is produced from fat cells or adipocytes.  The more fat a person has the more leptin a person will produce. And people who are obese are found to have two or three times higher risk of developing colon cancer.