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Omega-3 oil: Fish or pills?

A flood of scientific findings on fish oil points to a startling conclusion: Certain omega-3 fatty acids in the oil, consumed either from fish or fish-oil capsules, appear to offer as much protection against dying from coronary heart disease as do cholesterol-lowering drugs.

The evidence of fish oil's protective powers is so strong that the American Heart Association now urges everyone to eat at least two small 3-ounce servings of fish a week. That's particularly important after menopause in women and after age 45 or so in men, when coronary risk starts to rise.

Last fall the heart association advised people who already have heart disease to consume about 1 gram a day of the active ingredients in fish oil--omega-3s called EPA and DHA. To follow that recommendation, the average person would have to take at least some fish-oil pills. This is one of the few times that a major health organization has endorsed any dietary supplement for treating or preventing disease.

But consumers who want the coronary protection that those omega-3s can provide may have other questions:

• Who else needs the pills? Millions of Americans have increased coronary risk but no apparent heart disease. Our medical consultants say that fish-oil supplements may make sense for those people as well, depending on the extent of their risk for heart disease.

• Is fish safe? Young children and women who are nursing or pregnant or who may become pregnant should avoid or limit their intake of certain types of fish that can be contaminated, notably with mercury. Other people should vary their choices, frequently eat the species unlikely to contain contaminants (see Right fish, least risk), and sharply restrict their intake of the species with the most mercury, namely shark, swordfish, and king mackerel.

• Are fish-oil supplements safe and are their contents reliable? The federal Food and Drug Administration rarely monitors the composition and purity of dietary supplements. But our tests of 16 top-selling fish-oil supplements were CR Quick Take

Certain omega-3 fatty acids in fish oil can help prevent cardiovascular disease. The only way to get substantial amounts of those omega-3s is from fish or fish-oil supplements.

• Most people with normal heart risk should eat at least two small servings of fish a week. Young children and pregnant women should avoid or limit their intake of species that may be contaminated with pollutants; others should vary their choices and sharply limit intake of the worst offenders. If you don’t like fish, you could consume the equivalent amount of omega-3s from fish-oil pills: about 2 grams (two daily doses) a week.

• People with heart disease should consume about 1 gram a day of the omega-3s, from fish or fish-oil supplements, provided their doctor gives the OK.

• The more risk factors you have for heart disease, the more you should consider following the above advice for heart patients.

• Our tests of 16 leading pill brands found that all contained roughly as much omega-3s as their labels claimed, and none were contaminated or spoiled. (See Ratings). So choose them based mainly on price.


reassuring: All those pills contained roughly as much EPA and DHA as their labels promised. None showed evidence of spoilage, and none contained significant amounts of mercury, the worrisome PCBs, or dioxin.

So the choice boils down to price, and we found good news there, too: Two brands, Kirkland Signature Natural Fish Oil and Member’s Mark Omega 3 Fish Oil, each a CR Best Buy, supplied the desirable daily dosage for less than half to as little as a tenth of the cost of the other brands we tested.


FIVE-WAY PROTECTION

Studies suggest several possible mechanisms to explain how fish oil helps minimize the consequences of heart disease and perhaps prevent the disease in the first place:

• It may electrically stabilize the heart-muscle cells, reducing the likelihood that a heart attack will trigger an arrhythmia or potentially deadly heartbeat disturbance.

• It may fight inflammation, which makes arterial plaque deposits more likely to break apart, create blood clots, and thus trigger a heart attack.

• It may make certain blood cells less sticky and less likely to form clots.

• It may make the arteries more elastic, reducing the chance that increased blood pressure will cause plaque deposits to rupture.

• High doses can reduce blood levels of triglycerides, a fat that may increase heart-disease risk.


A DRAMATIC DROP IN DEATHS

The benefits of fish oil emerged when researchers noticed that people who ate fish frequently suffered fewer heart attacks and died of heart disease at a lower rate than those who seldom ate fish. Most significant, those studies showed that eating fish offers powerful protection against one of the most dreaded and unpredictable consequences of heart disease: "sudden-death" heart attacks that kill within minutes. Subsequent research suggested that high fish consumption may also reduce the risk of stroke.

Controlled clinical trials have confirmed that a steady diet of fish or fish-oil supplements works as "secondary prevention," reducing the likelihood of a repeat heart attack in people who’ve already had a first attack.

For example, the Diet and Reinfarction Trial, involving some 2,000 heart-attack survivors in Wales, found that those who increased their EPA and DHA intake from fish by at least 500 milligrams a day for two years had a 29 percent lower death rate than those who didn’t boost their fish intake; a drop in fatal heart attacks accounted for that entire benefit. Another trial, involving some 11,300 Italian heart-attack survivors followed for 3 1/2 years, found that those given 850 milligrams a day of EPA and DHA from supplements had 20 percent fewer deaths overall and 45 percent fewer sudden-death heart attacks than the untreated control group.

Long-term clinical trials of fish-oil supplements have not yet been conducted in one important group: people who have major risk factors for heart disease, such as diabetes or high blood pressure, but who haven’t developed any apparent signs of the disease. So researchers cannot be sure that taking these supplements would work as "primary prevention"--keeping a heart attack from occurring in the first place.

However, William S. Harris, Ph.D., professor of medicine at the University of Missouri and director of the Lipid and Metabolic Research Laboratory at the MidAmerica Heart Institute, notes, "There has never been a cardiologic treatment that worked as secondary prevention that didn’t also work as primary prevention."

Copyright © 2000-2006 Consumers Union of U.S., Inc. No reproduction, in whole or in part, without written permission.

I know. I am such a sucker for those terms "organic" "whole" "biotransformed" "energizing " "free-radical scavenging" ...

ruby wrote:我生完宝宝还坚持吃了1.2年prenatal维生素，后来就吃宝宝的gummy bear 维生素。最近听说的新trend是prenatal维生素加DHA,做成两片（dual装）或2in1.

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你跟我不能吃一种维生素。你得吃带叶酸的。

Knowing wrote:你跟我不能吃一种维生素。你得吃带叶酸的。

我老年纪见长，对自己的身体越来越爱惜，每天都要吞维生素和鱼油