Prostate cancer rates falling
The number of new cases of prostate cancer reported in the United States dramatically decreased between 1992 and 1993, according to new data.
An article in the University of California-BerkeleyWellness Letter states that the number of reported cases of prostate cancer dropped 16 percent among white men and rose 2 percent among black men. The decrease is a sharp contrast to previous years, when the number of new prostate cancer cases overall rose an average of 20 percent annually between 1989 and 1992. Between 1974 and 1989, the rate of new cases was only 3 percent annually.
Scientists say the increase between 1989 and 1992 might have been linked to an increase in early screening for prostate cancer.(3)
DHEA performs poorly in study
The most extensive study to date on the hormone DHEA shows that it doesn’t increase longevity.
DHEA stands for dehydroepiandrosterone, a natural hormone manufactured by the adrenal gland. It is also a popular supplement that many people take to increase their lifespans.
The study was funded by the National Cancer Institute and is the first to test the hormone on healthy animals with normal lifespans, according to the Center for Science in the Public Interest. Researchers at the University of Wisconsin-Madison found that DHEA didn’t help mice live longer. The researchers administered DHEA daily to 75 out of 150 mice, beginning when the mice entered middle age. Those that received the DHEA lived no longer than mice not given the hormone.
In another part of the study that is still under way, researchers put 150 mice on a restricted-calorie diet. Restricted-calorie diets have been shown to increase longevity. But, so far, seventy-five mice on the diet and taking DHEA seem to be dying earlier than those on the diet and not taking DHEA, the researchers reported. (4)
(1) “No Prostate Cancer Epidemic.” University of California Berkeley Wellness Letter April 1997, 13:7.
(2) Nutrition Action Health Letter March 1997, 24, 2:3.