After a point, more omega-3s don't help the heart

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NEW YORK | Mon May 31, 2010 10:21am EDT

NEW YORK (Reuters Health) - Memo to adults with heart disease: If you're already eating a fair amount of fish and taking omega-3 fatty acid supplements, the extra boost may not be doing much to help your heart.

New research suggests that only patients with very low daily intake of certain omega-3 fatty acids, found in fish and some plants and nuts, are likely to reduce their risk of heart attacks or death if they take more supplements rich in these fatty acids.

The study supports research which has shown that, after a certain point, omega-3 supplements may not do much for the heart. It also comes as a new U.S. Government Accountability Office urged more authority for the Food and Drug Administration to inspect the quality and safety of supplements, whose manufacturers often make claims not supported by data.

"Based on data from this and previous studies also in other countries, we think that it is relevant to say that most cardiac patients who are well medically treated and eat at least a certain amount of fish per week, probably will not benefit from taking omega-3 supplements," Mari Manger, the study's lead author and a PhD candidate at University of Bergen in Norway, told Reuters Health by e-mail.

The study, published in the American Journal of Clinical Nutrition, followed more than 2,400 Norwegians, about 80 percent of them men, being treated for heart disease. All were on cholesterol-lowering drugs.

At the beginning of the study, all patients filled out a questionnaire about their eating habits, including the fish products and supplements such as cod liver oil that they had eaten over the past year. From this, the authors calculated how much of three different kinds of omega-3 fatty acids thought to be associated with heart health the subjects were getting in their diets and supplements.

The authors then tracked the patients for an average of almost 5 years for heart-related complications, including heart attacks and death. Except for patients who consumed the lowest levels of omega-3s, there was no relationship between how much a person consumed and whether they suffered a heart attack or other complication.

Only two percent of patients in the study consumed levels of two kinds of omega-3s below the recommended level.

Eating more fish and taking more supplements didn't prevent heart problems, although high levels of omega-3s didn't hurt the patients either.

These results may be atypical, said Dr. Alice Lichtenstein, a nutritional scientist at Tufts University, because the Norwegian diet differs from that of, say, Americans, who rarely consume fish oil. "This study doesn't refute current recommendations for individuals to consume more fish," Lichtenstein, who was not involved with the study, told Reuters Health.

"The current data indicates that there's probably a threshold" of benefits for omega-3s, "and that's why the recommendation (from the American Heart Association) is two fish meals a week."

Source: here American Journal of Clinical Nutrition, May 19, 2010.

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Comments (3)
VitaminD3Man wrote:
The study is deeply flawed as it does not recognize confounding factors.

What were the patients’ 25 OH D (activated vitamin D) levels?

Were they at the now recognized healthy, natural norm of at least 50 ng/ml, 25 OH D?

Cod liver oil contains toxic levels of vitamin A. Whether one is aware of this very new finding is of no consequence regarding its confirmed toxic effect. In particular certain forms of vitamin A (retinoic acid) are toxic especially in current cod liver formulations.Simply there is too much vitamin A and nearly always too little vitamin D.

Vitamin A can interfere with vitamin D receptors thus thwarting D’s know ability to fight heart disease.

Americans on average consume excessive, dangerous amounts of Omega 6 and 9. It is estimated that Omega 6 and 9 consumption is 40 times that of daily Omega 3 fatty acids. This is unhealthy and detrimental to human health in numerous ways.

To say that taking a few Omega 3 supplements per day (1000 mg supplements) will in some way “top out’ dietary needs is misleading, if not dangerous medical advice. Even 3-4 grams daily Omega 3 will not offset the vastly larger qunatities consumed on average in bakery and processed food products.

Continue to take Omega 3 supplements to offset the saturation of Omega 6 and 9 in nearly all processed and baked foods. At worst it can do no harm and at best reduce chronic disease.

May 31, 2010 11:29am EDT  --  Report as abuse
VinK wrote:
This report is dangerous to headline-skimmers who do not have the full context.

The study was done on Norwegians, who consume 5X more of Omega-3 in their diet than Americans.

Americans are grossly deficient in Omega-3. Americans average about 100 mg of Omega-3 per day. The American Heart Association recommends about 10X that much.

Eating seafood and supplementing with pharmaceutical grade fish oil like this: http://www.omegavia.com or Nordic Naturals are both highly recommended.

And remember, the amount of Omega-3 required to address inflammation and mood disorders is quite high.

A recent study, also published in the same journal looked at Yupik Eskimos and the authors found that ‘Very high Omega-3 intakes were linked to big health benefits.’ See for yourself: http://tinyurl.com/286u2lj

May 31, 2010 3:38pm EDT  --  Report as abuse
Aarky wrote:
Drat!! I have suffered through all the trendy thinking on Vitamins A,C, and E, plus Folic Acid, only to find out that they could actually be harmful or useless. The newest hype is about more vitamin D. I have taken Omega 3 in the form of canola oil for 15 years. I took cherry flavored cod liver oil, but couldn’t stand the burp taste of cherry flavored cod oil. Three tablespoons a day of the canola oil has kept my HDL in the 40’s range. Now along comes someone who says it probably doesn’t protect. What next??

HQAVE3 f

Jun 01, 2010 12:06pm EDT  --  Report as abuse
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