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chaloobi
SFN Regular
1620 Posts |
 Posted - 06/19/2008 : 05:02:20
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Interesting.
Healthy lifestyle triggers genetic changes: study
By Will Dunham
WASHINGTON (Reuters) - Comprehensive lifestyle changes including a better diet and more exercise can lead not only to a better physique, but also to swift and dramatic changes at the genetic level, U.S. researchers said on Monday.
In a small study, the researchers tracked 30 men with low-risk prostate cancer who decided against conventional medical treatment such as surgery and radiation or hormone therapy.
The men underwent three months of major lifestyle changes, including eating a diet rich in fruits, vegetables, whole grains, legumes and soy products, moderate exercise such as walking for half an hour a day, and an hour of daily stress management methods such as meditation.
As expected, they lost weight, lowered their blood pressure and saw other health improvements. But the researchers found more profound changes when they compared prostate biopsies taken before and after the lifestyle changes.
After the three months, the men had changes in activity in about 500 genes -- including 48 that were turned on and 453 genes that were turned off.
The activity of disease-preventing genes increased while a number of disease-promoting genes, including those involved in prostate cancer and breast cancer, shut down, according to the study published in the journal Proceedings of the National Academy of Sciences.
The research was led by Dr. Dean Ornish, head of the Preventive Medicine Research Institute in Sausalito, California, and a well-known author advocating lifestyle changes to improve health.
"It's an exciting finding because so often people say, 'Oh, it's all in my genes, what can I do?' Well, it turns out you may be able to do a lot," Ornish, who is also affiliated with the University of California, San Francisco, said in a telephone interview.
"'In just three months, I can change hundreds of my genes simply by changing what I eat and how I live?' That's pretty exciting," Ornish said. "The implications of our study are not limited to men with prostate cancer."
Ornish said the men avoided conventional medical treatment for prostate cancer for reasons separate from the study. But in making that decision, they allowed the researchers to look at biopsies in people with cancer before and after lifestyle changes.
"It gave us the opportunity to have an ethical reason for doing repeat biopsies in just a three-month period because they needed that anyway to look at their clinical changes (in their prostate cancer)," Ornish said.
(Editing by Julie Steenhuysen and Xavier Briand) |
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-Chaloobi
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tomk80
SFN Regular
Netherlands
1278 Posts |
Posted - 06/19/2008 : 06:15:22 [Permalink]
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| This study rocks. |
Tom
`Contrariwise,' continued Tweedledee, `if it was so, it might be; and if it were so, it would be; but as it isn't, it ain't. That's logic.'
-Through the Looking Glass by Lewis Caroll- |
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Hawks
SFN Regular
Canada
1383 Posts |
Posted - 06/19/2008 : 06:38:56 [Permalink]
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| To avoid any confusion, I think it is important to stress that it is gene expression that that can change. Can't say I'm too surprised. |
METHINKS IT IS LIKE A WEASEL
It's a small, off-duty czechoslovakian traffic warden! |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 06/19/2008 : 06:54:08 [Permalink]
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The study abstract reminds that this is a pilot study, and more research is needed. It would be great if the results are confirmed, but I have my doubts.
Quackwatch has this to say about Ornish:Dean Ornish, MD earned his reputation with his work on the management of atherosclerosis with extremely low fat vegetarian diets. But like predecessor Nathan Pritikin, Ornish's recommendations are not suitable for most people. The few small studies claimed to prove the worth of his work have also been questioned on scientific grounds. Dr. Richard Pasternak, director of preventive cardiology at the Massachusetts General Hospital in Boston, has said that "There's virtually no science" in them [117]. Dr. Robert Eckel, Professor of Medicine at the University of Colorado Health Sciences Center in Denver and chairman of the nutrition committee of the American Heart Association also expressed serious doubts, as did Dr. Frank Sacks, a nutrition professor at Harvard Medical School and the Harvard School of Public Health. Dr. Sacks, in trying to replicate Dr. Ornish's results with a grant from the NIH, found that it was difficult to recruit patients and few could stick with the program [118]. Fortunately, Ornish's program has been superseded by more effective forms of managing elevated blood cholesterol and the discovery of other treatable risk factors.
Like Dr. Gordon, Dr. Ornish began as a devotee of an Indian guru, Sri Swami Satchidananda. He became involved with the Swami after dropping out of Rice University in 1972 in a state of suicidal depression. It was apparently during this time that he formed his beliefs about the importance of a vegetarian diet with no added salt, sugar or fat and no caffeine combined with meditation, yoga and exercise.
Dr. Ornish has enthusiastically endorsed many irresponsible unscientific works by others including Larry Dossey's Healing Words [119], and psychic Judith Orloff's Second Sight" [120]. Dr. Gordon's own Center for Mind-Body Medicine features an endorsement by Ornish as well [121]. |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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Dude
SFN Die Hard
USA
6891 Posts |
Posted - 06/19/2008 : 06:57:43 [Permalink]
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Whats interesting is the number of genes this study looked at and found to be regulated. Its well established that diet/excercise effects the expression of some genes, but the scope of this study demonstrates that lifestyle can have a very significant impact on a large number of genes and their expression.
Its probably just the tip of the iceberg too.
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Ignorance is preferable to error; and he is less remote from the truth who believes nothing, than he who believes what is wrong.
-- Thomas Jefferson
"god :: the last refuge of a man with no answers and no argument." - G. Carlin
Hope, n.
The handmaiden of desperation; the opiate of despair; the illegible signpost on the road to perdition. ~~ da filth |
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Zebra
Skeptic Friend
USA
354 Posts |
Posted - 06/21/2008 : 00:13:22 [Permalink]
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Interesting.
I read the paper (like the marketers say, "so you don't have to!"). As Dave W. says, it's a pilot study. The authors appropriately indicate they are aware of multiple limitations & that more research is necessary.
This pilot study is messy, in that it included a whole slew of difficult interventions & multiple types of lifestyle & diet changes. The intervention started with a "3-day intensive residential retreat" then 3 months with: 1 hr/dy of "stress management", walking 30 min/dy x 6 dys/wk, 1 hr/wk group support session, and 1 phone call/wk with research RN. All food for the 3 months was provided to the study participants. And it wasn't just food - the diet was supplemented with: vitamin E (100 IU/dy), selenium 200 mg/dy, vitamin C (2 gm/dy), fish oil (3 gm/dy), and soy (tofu at 1 meal/day, plus 58 gm/dy of soy protein).
Each participant served as his own control. The studies on mRNA (gene expression) were done on normal prostate tissue, as fewer than 1/3 of these men (all of whom had low-grade prostate cancer, biopsy-proven before entry into the study) had cancer cells on the 2 biopsies taken for this study, at entry and at 3 months. (That does NOT mean their cancers regressed during the study. Only 1 patient had a change in clinical staging of his cancer during the 3 months, & that was for the worse.) IMO, one weakness was that the change in gene expression might simply change over time. Bigger problem is that any one of the interventions from this study could be responsible for any portion of the effect seen, or it could be due to weight loss without regard to how the weight loss was brought about.
The participants all lost weight (BMI declined an average of 2.6 in 3 months, from average of 26.6 at baseline, example would be a 5'9" man dropping from 180 lbs to 163 lbs, a loss of 5.6 lbs/month - quite dramatic). Total cholesterol dropped an average of 45 points, systolic BP an average of 10 mm Hg, oh and "intrusive thoughts" and "avoidance" scores dropped on the "Impact of Event" score they used [where Diagnosis with Cancer, then Living with Cancer = the Event].
The authors reference 2 papers (of several in the literature) which reported changes in gene expression in adipocytes, one with changes in diet (type of carbohydrate source, basically glycemic index) and the other with caloric restriction. I found another which reported changes in adipocyte gene expression related to caloric restriction but not to dietary fat content. So, changes in ONE component of diet...or weight loss alone, regardless of how it's achieved...could affect gene regulation. [A recent study reported a 76% reduction in cancer diagnoses in the 5 yrs after bariatric surgery, in 1035 obese people vs. ~5700 controls. Weight loss itself may have a very significant effect on gene expression for tumorigenesis. 'Course, this study raises its own questions, like were the people who underwent surgery more likely to have screening for cancer before surgery than the controls.]
Another problem is the supplements Ornish et al. included in the diet. There's at least one study going on now investigating vitamin E and selenium for potential prevention of prostate cancer. Soy, a phytoestrogen, may reduce the risk of localized prostate cancer. There's interest in vitamin C and fish oil for prevention or slowing of prostate cancer (less data than on the other supplements). So, any one of these agents, or any combination, or the whole kit and caboodle, could have been responsible for the majority of the changes seen.
(The authors indicate that the mRNAs they tested are a panel previously reported to be from genes relevant to tumorigenesis...reassuring, because one of my first questions was whether they were just data mining, looking for ANY changes without having a clue as to whether or not those changes could be meaningful.)
[Edited to remove an extra word which made no sense at all] |
I think, you know, freedom means freedom for everyone* -Dick Cheney
*some restrictions may apply |
| Edited by - Zebra on 06/21/2008 00:16:06 |
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RadioMusicBox
New Member
USA
15 Posts |
Posted - 06/22/2008 : 17:04:02 [Permalink]
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| This article is very interesting. |
It's a cruel world...and YOU SUCK!!!!! (LAUGHTER) |
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Affect Your Genetics with Lifestyle?
