Featured Research

from universities, journals, and other organizations

Omega 3: What is good for the heart may not be good for the prostate, study suggests

Date:
April 25, 2011
Source:
Fred Hutchinson Cancer Research Center
Summary:
The largest study to examine the association of dietary fats and prostate cancer risk has found what's good for the heart may not be good for the prostate. A U.S. nationwide study involving more than 3,400 men found those with the highest blood percentages of DHA, an inflammation-lowering omega-3 fatty acid commonly found in fatty fish, have more than twice the risk of developing aggressive, high-grade prostate cancer compared to men with the lowest DHA levels.

The largest study ever to examine the association of dietary fats and prostate cancer risk has found what's good for the heart may not be good for the prostate.

Related Articles


Analyzing data from a nationwide study involving more than 3,400 men, researchers at Fred Hutchinson Cancer Research Center found that men with the highest blood percentages of docosahexaenoic acid, or DHA, an inflammation-lowering omega-3 fatty acid commonly found in fatty fish, have two-and-a-half-times the risk of developing aggressive, high-grade prostate cancer compared to men with the lowest DHA levels.

Conversely, the study also found that men with the highest blood ratios of trans-fatty acids -- which are linked to inflammation and heart disease and abundant in processed foods that contain partially hydrogenated vegetable oils -- had a 50 percent reduction in the risk of high-grade prostate cancer. In addition, neither of these fats was associated with the risk of low-grade prostate cancer risk. The researchers also found that omega-6 fatty acids, which are found in most vegetable oils and are linked to inflammation and heart disease, were not associated with prostate cancer risk. They also found that none of the fats were associated with the risk of low-grade prostate cancer.

These findings by Theodore M. Brasky, Ph.D., and colleagues in the Hutchinson Center's Public Health Sciences Division were published online April 25 in the American Journal of Epidemiology.

"We were stunned to see these results and we spent a lot of time making sure the analyses were correct," said Brasky, a postdoctoral research fellow in the Hutchinson Center's Cancer Prevention Program. "Our findings turn what we know -- or rather what we think we know -- about diet, inflammation and the development of prostate cancer on its head and shine a light on the complexity of studying the association between nutrition and the risk of various chronic diseases."

The researchers undertook the study because chronic inflammation is known to increase the risk of several cancers, and the omega-3 fatty acids found primarily in fish and fish oil supplements have anti-inflammatory effects. In contrast, other fats, such as the omega-6 fats in vegetable oil and trans-fats found in fast foods, may promote inflammation. "We wanted to test the hypothesis that the concentrations of these fats in blood would be associated with prostate cancer risk," Brasky said. "Specifically, we thought that omega-3 fatty acids would reduce and omega-6 and trans-fatty acids would increase prostate cancer risk."

The mechanisms behind the impact of omega-3s on risk of high-grade prostate cancer are unknown. "Besides inflammation, omega-3 fats affect other biologic processes. It may be that these mechanisms play a greater role in the development of certain prostate cancers," Brasky said. "This is certainly an area that needs more research."

Currently there is no official recommended daily allowance for omega-3 fats for adults or children, although many nutrition experts and physicians recommend 450 milligrams of omega-3 DHA per day as part of a healthy diet.

The study was based on data from the Prostate Cancer Prevention Trial, a nationwide randomized clinical trial that tested the efficacy of the drug finasteride to prevent prostate cancer. While the trial involved nearly 19,000 men age 55 and older, the data in this analysis came from a subset of more than 3,000 of the study participants, half of whom developed prostate cancer during the course of the study and half of whom did not. The clinical trial was unique in that prostate biopsy was used to confirm the presence or absence of prostate cancer in all study participants.

Among the study participants, very few took fish oil supplements -- the most common non-food source of omega-3 fatty acids, which are known to prevent heart disease and other inflammatory conditions. The majority got omega 3s from eating fish.

So based on these findings, should men concerned about heart disease eschew fish oil supplements or grilled salmon in the interest of reducing their risk of aggressive prostate cancer? Brasky and colleagues don't think so.

"Overall, the beneficial effects of eating fish to prevent heart disease outweigh any harm related to prostate cancer risk," Brasky said. "What this study shows is the complexity of nutrition and its impact on disease risk, and that we should study such associations rigorously rather than make assumptions," Brasky said.

The National Cancer Institute funded this study, which also involved researchers from the University of Texas Health Science Center at San Antonio and the NCI.


Story Source:

The above story is based on materials provided by Fred Hutchinson Cancer Research Center. Note: Materials may be edited for content and length.


Journal Reference:

  1. Phyllis Goodman, Ian M. Thompson, Irena B. King, Demetrius Albanes, and Alan R. Kristal. Serum Phospholipid Fatty Acids and Prostate Cancer Risk: Results From the Prostate Cancer Prevention Trial. Am. J. Epidemiol., April 24, 2011 DOI: 10.1093/aje/kwr027

Cite This Page:

Fred Hutchinson Cancer Research Center. "Omega 3: What is good for the heart may not be good for the prostate, study suggests." ScienceDaily. ScienceDaily, 25 April 2011. <www.sciencedaily.com/releases/2011/04/110425135643.htm>.
Fred Hutchinson Cancer Research Center. (2011, April 25). Omega 3: What is good for the heart may not be good for the prostate, study suggests. ScienceDaily. Retrieved November 28, 2014 from www.sciencedaily.com/releases/2011/04/110425135643.htm
Fred Hutchinson Cancer Research Center. "Omega 3: What is good for the heart may not be good for the prostate, study suggests." ScienceDaily. www.sciencedaily.com/releases/2011/04/110425135643.htm (accessed November 28, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, November 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Rural India's Low-Cost Sanitary Pad Revolution

Rural India's Low-Cost Sanitary Pad Revolution

AFP (Nov. 28, 2014) — One man hopes his invention -– a machine that produces cheap sanitary pads –- will help empower Indian women. Duration: 01:51 Video provided by AFP
Powered by NewsLook.com
Research on Bats Could Help Develop Drugs Against Ebola

Research on Bats Could Help Develop Drugs Against Ebola

AFP (Nov. 28, 2014) — In Africa's only biosafety level 4 laboratory, scientists have been carrying out experiments on bats to understand how virus like Ebola are being transmitted, and how some of them resist to it. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
WHO Says Male Ebola Survivors Should Abstain From Sex

WHO Says Male Ebola Survivors Should Abstain From Sex

Newsy (Nov. 28, 2014) — WHO cites four studies that say Ebola can still be detected in semen up to 82 days after the onset of symptoms. Video provided by Newsy
Powered by NewsLook.com
Ebola Leaves Orphans Alone in Sierra Leone

Ebola Leaves Orphans Alone in Sierra Leone

AFP (Nov. 27, 2014) — The Ebola epidemic sweeping Sierra Leone is having a profound effect on the country's children, many of whom have been left without any family members to support them. Duration: 01:02 Video provided by AFP
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:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

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