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PostPosted: Thu Aug 27, 2009 10:08 pm 
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I'm going to paste a rather long article here, because I think you would need a membership in the site it appeared on in order to access it. They provided "print" and "mail to" links, so I don't think they have big issues with copyright. It is a continuing medical education site (I earned 0.25 of a credit for reading it). I thought that this was of particular interest, because it reflects changes in the thinking of main-line physician groups, which is gratifying.

Here it is:

August 7, 2009 — A new review concludes that there is extensive evidence from three decades of research that fish oils, or more specifically the omega-3 polyunsaturated fatty acids (PUFAs) contained in them, are beneficial for everyone [1].

This includes healthy people as well as those with heart disease — including postmyocardial infarction (MI) patients and those with heart failure, atherosclerosis, or atrial fibrillation — say Dr Carl J Lavie (Ochsner Medical Center, New Orleans, LA) and colleagues in their paper published online August 3, 2009, in the Journal of the American College of Cardiology.

"We reviewed everything that was published on omega-3 that was clinically important, and the major finding is that there are a tremendous amount of data to support the benefits of omega-3, not just as a nutritional supplement — people have known that for years — but evidence that it prevents and treats many aspects of cardiovascular disease," Lavie told heartwire .

Lavie said he believes clinicians are not as familiar with the omega-3 studies as they should be: "Clinicians know the findings of many statin trials even if they do not know all the details — they know that there are a ton of statin data. The omega-3 data may not be as impressive or as plentiful as this, but it should be 'promoted' to clinicians."

Omega-3 PUFA, says Lavie, "is a therapy that clinicians should be considering prescribing to their patients. Not just as something healthy but as something that may actually prevent the next event. In HF [heart failure], it may prevent death or hospitalization and the same thing post-MI." He and his colleagues reiterate the advice of the American Heart Association (AHA): that those with known coronary heart disease (CHD) or HF eat four or five oily-fish meals per week or take the equivalent in omega-3 supplements; healthy people should consume around two fatty-fish meals per week or the same in supplements.

Most Data on EPA and DHA

In their review, Lavie and colleagues explain that most of the data on omega-3 have been obtained in trials using docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), the long-chain fatty acids in this family. The most compelling evidence for cardiovascular benefits comes from four controlled trials of almost 40,000 participants randomized to receive EPA with or without DHA in studies of primary prevention, after MI, and most recently with HF, they note.

They discuss the results for each specific cardiovascular condition in turn. For CHF, three large randomized trials — the Diet and Reinfarction Trial (DART), the Gruppo Italiano per lo Studio della Sopravvivenza nell' Infarto Miocardico (GISSI)-Prevenzione, and the Japan EPA Lipid Intervention Study (JELIS) — have indicated that omega-3 PUFAs lower CV risk in both the primary- and secondary-prevention settings, they note.

Lavie elaborated to heartwire : "The benefit is different in different studies but can be as much as 30%." The effects are seen on total mortality, sudden death, CHD mortality, and cardiovascular mortality.

But there are some studies that have not shown favorable results, although there are generally methodological reasons for this, they say. However, they do flag the most recent study of post-MI patients, OMEGA, which suggests there may not be additional short-term benefit of omega-3 PUFAs in low-risk patients already receiving optimal modern therapy.

There is also evidence of benefit in atherosclerosis and in a wide range of arrhythmias, with the most significant effect and potential benefit seen in "the current epidemic" of atrial fibrillation (AF), note the researchers. But more studies are needed to explore the effects of various doses of omega-3 PUFAs on the primary and secondary reduction of AF and to determine whether the benefits are caused by antiarrhythmic effects, benefits on autonomic tone, or even anti-inflammatory effects, they observe.

Benefit of Fish Oils Also Extends to HF

Recently, the potential benefits of omega-3 PUFAs "have been extended to the prevention and treatment of HF," say Lavie et al. Although the reduction in events was "only 8% to 9% in the recent GISSI-HF trial, which is not huge," Lavie admits, "when you think of HF, it's a very serious disorder, and in GISSI-HF, those patients were treated vigorously for their HF, so they were on good therapy, and adding just one [omega-3 PUFA] pill a day reduced deaths by between 8% and 9%, which is a pretty nice additional benefit."

But he and his colleagues say further studies are needed to determine the optimal dosing of omega-3 PUFA for different stages of HF and to investigate the underlying mechanisms for the benefits. However, in the meantime, omega-3 PUFA supplements "should join the short list of evidence-based life-prolonging therapies for HF."

They also discuss the data on omega-3 PUFAs in hyperlipidemia, noting that the FDA has approved one such supplement for the treatment of very high triglyceride levels.

And they note that more studies are needed to determine the optimal mix of DHA relative to EPA in various populations.

Finally, they state that this review does not focus on the plant-based precursor of EPA, alpha-linolenic acid (ALA), which is found in abundance in flaxseed and to a lesser extent in other plants. But they observe "the overall evidence is much weaker for ALA than for EPA and DHA."

Recommendations for Omega-3 Consumption

Mirroring recommendations from the AHA, European Society of Cardiology, and the World Health Organization (WHO), Lavie and colleagues recommend that healthy people consume at least 500 mg per day of EPA/DHA — equal to around two fatty-fish meals per week — and that those with known CHD or HF get 800 to 1000 mg per day EPA/DHA.

Asked by heartwire whether people should try to consume more fish or alternatively take supplements, Lavie says: "If somebody really were eating salmon and tuna and mackerel and sardines, and they were doing that several times a week, then they wouldn't need to be taking a supplement. But in the US, at least, very few people are going to eat the therapeutic doses of fatty fish."

Other good reasons to take supplements include the fact that they have usually had impurities, such as mercury, removed, he notes.

If people are trying to improve their consumption of oily fish, they could take supplements only on the days they were not eating such fish or every other day to try to get up to the recommended amount of omega-3 PUFAs, Lavie says.

But he warns that regimens that are too complex might result in underconsumption: "I would tend to think that most people are getting very little omega-3 PUFAs in the diet. There's no harm in taking extra — the only negative of extra is the calories. I don't think anyone thinks now that fish oil is doing any harm."

Dr. Lavie has been a consultant and speaker for Reliant, Pfizer, Bristol-Myers Squibb, and Sanofi-Aventis and is a speaker receiving honoraria from and on the speaker's bureau of GlaxoSmithKline, Abbott, and Solvay. Disclosures for the coauthors are listed in the article.

Reference

1. Lavie CJ, Milani RV, Mehra MR, et al. Omega-3 polyunsaturated fatty acids and cardiovascular disease. J Am Coll Cardiol 2009; 54: 585-594. Available at: http://content.onlinejacc.org.

Clinical Context

Fish oil is obtained by eating oily fish such as herring, mackerel, salmon, and sardines or by consuming fish oil supplements or cod liver oil. Most of the evidence for benefits suggests that the most important oils are EPA and DHA comprising the omega-3 PUFAs. The AHA currently endorses use of omega-3 PUFA at 1 g/day of combined EPA and DHA in the form of fatty fish or fish oil supplements (in capsule or liquid form) in patients with CHD for secondary prevention. The mechanism of action of EPA-DHA appears to be a combination of enrichment of membrane phospholipids, vasodilatation, blood pressure reduction, improvement of endothelial function, and reduction in platelet aggregation. For primary prevention, the AHA recommends 2 oily fish meals weekly.

This is a review of recent studies on the use of omega-3 PUFA for primary and secondary cardiovascular disease prevention to identify the benefits and optimal doses.


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PostPosted: Fri Aug 28, 2009 3:31 am 
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That's always good to see progress being made.


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PostPosted: Fri Aug 28, 2009 7:51 am 
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I see this as important, mainly as indication that the medical comunity is starting to take this seriously. In my opinion, too often this type of message is drowned out by the flood of research into expensive drugs like statins. It's not the weight of the evidence but the weight of the research that has the impact. No one is going to get rich promoting fish oil over statins so this is all the more reason that this type of research should be given more credance.


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PostPosted: Fri Aug 28, 2009 8:01 am 
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I hope you're right.

My dad has heart problems, i believe nothing serious just now, but he's high risk. I suggested fish oil. With good faith, I said, "you should take fishoil, daily, but check with your dietician first". The dietician rubbished them, said, "if you eat fish, there's on need to take fish oil" and the best part was that vitamin/mineral/fat supplements generally 'don't work'.

I said, "let me guess, was your dietician fat?" He started laughing quite histerically, which means yes. I said, "I know you like fish but do you eat it every day? Even every week?". He just said, "no but I think i'll follow the dieticians advice".

* bangs head off wall repeatedly *

KPj


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PostPosted: Fri Aug 28, 2009 8:54 am 
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Just because enlightened Docs like our jungle friend reads this type of article doesn't mean all dietitians do. After all, it wasn't in their university text book. It will probably take a generation to hit that level.

I'm having similar issues with my daughter's Ulcerative Colitis. The Dietitian advice is useless and the doctor doesn't want to listen to anything not supported with copious research. Therefore she's on expensive medicines with potentially fatal side effects while cheap safe alternative therapies are ignored.

Edited for spelling. It's hard to believe I'm educated.


Last edited by stuward on Sat Aug 29, 2009 8:44 am, edited 1 time in total.

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PostPosted: Fri Aug 28, 2009 11:15 pm 
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KPj--The author of the paper did acknowledge that it's unlikely for people to actually get enough fish to make a difference, and suggested that one should at least take fish oil on days when there is no fish in the diet. I hope KPs changes his mind.


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PostPosted: Tue Sep 01, 2009 11:13 am 
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Me too. I actually emailed him the article, but I doubt he'll read it.

Funnily enough Cressey posted the following research on his blog on Friday, on Vitamin D (which I also take daily). There's loads of research on that now too. I never took it for any specific reason other than - too many people I respect talk about it too much for it to be useless.

http://www.netrition.com/cgi/news.cgi?f ... 24070700_0

Sent him that too. Sometimes I think he's starting to want to hear what i've got to say. Ever since my sisters improvement (I still train her, and she's looking great). We'll see.....


KPj


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