Featured Research

from universities, journals, and other organizations

Exposure To Sunlight May Decrease Risk Of Prostate Cancer

Date:
June 24, 2005
Source:
Wake Forest University Baptist Medical Center
Summary:
In the largest such study to date, a research team from three cancer centers measured sunlight exposure in men and found that increased exposure to sunlight may decrease the risk of prostate cancer.

WINSTON-SALEM, N.C. -- In the largest such study to date, a research team from three cancer centers measured sunlight exposure in men and found that increased exposure to sunlight may decrease the risk of prostate cancer.

Reporting in the June 15 issue of Cancer Research, the researchers, led by Esther John, Ph.D., of the Northern California Cancer Center, and including Sue Ingles, Ph.D., of the Keck School of Medicine of the University of Southern California, and Gary G. Schwartz, Ph.D., of the Comprehensive Cancer Center of Wake Forest University, found that men with high sun exposure had half the risk of prostate cancer than did men with low sun exposure.

They said in men with certain gene variants, risk was reduced even further, to as much as 65 percent.

"We believe that sunlight helps to reduce the risk of prostate cancer because the body manufactures the active form of vitamin D from exposure to sunlight," John said.

Previous research by Schwartz and his colleagues had shown that the prostate uses vitamin D to promote the normal growth of prostate cells and to inhibit the invasiveness and spread of prostate cancer cells to other parts of the body.

"The genes involved are those that determine the type of vitamin D receptors a person has," said Schwartz. "These receptors, which function with vitamin D like a lock and key, vary in their ability to bind vitamin D and thus to influence cell behavior."

The researchers stressed that sunlight is not the only source of vitamin D, and that men should not try to reduce their risk of prostate cancer by sunbathing because that increases the risk of sun-induced skin cancer, especially melanoma.

"If future studies continue to show reductions in prostate cancer risk associated with sun exposure, increasing vitamin D intake from diet and supplements may be the safest solution to achieve adequate levels of vitamin D," they said.

The researchers compared 450 non-Hispanic white patients in the San Francisco Bay area who had advanced prostate cancer with a matched control group of 455 men who did not have prostate cancer. They defined advanced prostate cancer as cancer that had penetrated through the prostate capsule either to the same region of the body or spread to distant sites.

The scientists measured sun exposure by comparing pigmentation of underarm skin, which is usually not exposed to sunlight, with forehead pigmentation, which is, using a portable reflectometer. Because it is hard for the sun to reach the underarm area, there was no difference in the underarm measurement between the prostate cancer cases and the control group. But when the forehead color was compared to the underarm color, the control group had significantly darker pigmentation than the cancer patients.

"Increasing darkness was associated with a trend of decreasing risk of prostate cancer," they said. The scientists also obtained a sun exposure history from each participant so they could track outdoor activity.

"Reduced risk of advanced prostate cancer was associated with high sun exposure determined by reflectometry and high occupational outdoor activity," they said. "Further studies in large populations, including non-whites, are warranted to confirm the combined effects of sun exposure and genotype and define the exposure period that is important in influencing prostate cancer risk."

David Van Den Berg, Ph.D., of the University of Southern California also participated in the study. The work was supported by the Cancer Research Fund of the California Department of Health Services.


Story Source:

The above story is based on materials provided by Wake Forest University Baptist Medical Center. Note: Materials may be edited for content and length.


Cite This Page:

Wake Forest University Baptist Medical Center. "Exposure To Sunlight May Decrease Risk Of Prostate Cancer." ScienceDaily. ScienceDaily, 24 June 2005. <www.sciencedaily.com/releases/2005/06/050623001030.htm>.
Wake Forest University Baptist Medical Center. (2005, June 24). Exposure To Sunlight May Decrease Risk Of Prostate Cancer. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2005/06/050623001030.htm
Wake Forest University Baptist Medical Center. "Exposure To Sunlight May Decrease Risk Of Prostate Cancer." ScienceDaily. www.sciencedaily.com/releases/2005/06/050623001030.htm (accessed September 17, 2014).

Share This



More Health & Medicine News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Artificial Sweetener Could Promote Diabetes

Artificial Sweetener Could Promote Diabetes

Newsy (Sep. 17, 2014) Doctors once thought artificial sweeteners lacked the health risks of sugar, but a new study says they can impact blood sugar levels the same way. Video provided by Newsy
Powered by NewsLook.com
Ebola Vaccine Trial Gets Underway at Oxford University

Ebola Vaccine Trial Gets Underway at Oxford University

AFP (Sep. 17, 2014) A healthy British volunteer is to become the first person to receive a new vaccine for the Ebola virus after US President Barack Obama called for action against the epidemic and warned it was "spiralling out of control." Duration: 01:02 Video provided by AFP
Powered by NewsLook.com
Obesity Rates Steady Even As Americans' Waistlines Expand

Obesity Rates Steady Even As Americans' Waistlines Expand

Newsy (Sep. 17, 2014) Researchers are puzzled as to why obesity rates remain relatively stable as average waistlines continue to expand. Video provided by Newsy
Powered by NewsLook.com
President To Send 3,000 Military Personnel To Fight Ebola

President To Send 3,000 Military Personnel To Fight Ebola

Newsy (Sep. 16, 2014) President Obama is expected to send 3,000 troops to West Africa as part of the effort to contain Ebola's spread. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins