Posted on 04/25/2011 7:14:47 PM PDT by decimon
Conversely, high percentage of trans-fatty acids linked with lower risk
SEATTLE – 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.
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.
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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.
At Fred Hutchinson Cancer Research Center, our interdisciplinary teams of world-renowned scientists and humanitarians work together to prevent, diagnose and treat cancer, HIV/AIDS and other diseases. Our researchers, including three Nobel laureates, bring a relentless pursuit and passion for health, knowledge and hope to their work and to the world. www.fhcrc.org
Ping
“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.”
Health, in two words: dynamic equilibrium.
Health, in one word: balance.
Can we just go back to eating what we want, hunh? Can we, can we?
Kinetic equilibrium?
If high omega-3 intake from fatty fish is a risk factor for aggressive prostate cancer, I would expect a high incidence among Japanese males.
Yet from what I find on the web, prostate cancer incidence in Japan is among the lowest in the world.
Other factors may be involved; one source said isoflavinoids (soy) may protect against prostate cancer.
When the food speakeasies start opening.
>> Can we just go back to eating what we want, hunh? Can we, can we?
Yes, you have permission, as long as you promise to worry yourself to death over it. :-)
Well this is just great, I finally had an evidence based supplement to take.
Yet from what I find on the web, prostate cancer incidence in Japan is among the lowest in the world.
Other factors may be involved; one source said isoflavinoids (soy) may protect against prostate cancer.
The Japanese Paradox?
THIS could be part of the issue with the study....having gone thru all this with my husband....who ended up getting HIFU in Mexico (because the FDA is JUST starting to look into it)....his HIFU doc felt biopsies are really a shot in the dark and NOT the best way to go. And, I also wonder WHICH trans fats they are talking about?
On the OTHER hand.....maybe this description of "trans fats" is why they work....they are the "poison" that keeps the "bad stuff" AWAY from the gland??? The problem with trans fats is that while the "business end" (the chemically active part) is messed up, the "anchor end" (the part that is attached to the cell wall) is unchanged. So they take up their position in the cell wall, like a guard on the fortress wall. But like a bad guard, they don't do their job! They let foreign invaders pass unchallenged, and they stop supplies at the gates instead of letting them in.
"In other words, trans fats are poisons, just like arsenic or cyanide. They interfere with the metabolic processes of life by taking the place of a natural substance that performs a critical function. And that is the definition of a poison. Your body has no defense against them!"
>> The Japanese Paradox?
I heard from some of my Japanese friends who smoke that smoking is not as dangerous for Japanese because their lungs are different and less prone to lung cancer.
They weren’t joking; they really believe that.
I might be high in both types of fat. Can't guess at if that's good or bad.
>> I finally had an evidence based supplement to take.
Maybe the caplets are OK, but just avoid the suppositories?
I don’t know how much iodine is in Omega 3 supplements but it has been posited that the Japanese have less prostate and breast cancer because of the iodine in the fish.
Have they changed the phrasing in biology textbooks since I last opened one?
They weren’t joking; they really believe that.
I think they're right about the lung cancer rate being lower despite smoking. Don't know if there's anything more than speculation to account for that.
I was trying to spoof Obama's "kinetic military operations."
Truer words never spoken. Which is why they will be generally ignored by all of those in the "scientific community" with their own axes to grind.
And as it is appointed unto men once to die, but after this the judgment:
Hebrews 9:27
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