Fish oil is a great catch for heart health
PHILADELPHIA - Americans love their fish oil - and so do many of their doctors, which makes this "natural" remedy different from most others.
That's because it has something other healing products in the marketplace lack: Science behind its health claims.
Studies show that the omega-3 fatty acids in fish oil can reduce heart-attack risk by preventing blood clots and abnormal heart rhythms, which cause sudden death.
It tastes a little fishy and sometimes causes burping or diarrhea. And because of its apparent blood-thinning effects, it's not a good fit for patients on prescription blood thinners or headed into surgery. But for people concerned about their heart, and for the doctors who treat them, fish oil may be a great catch.
"There's definitely a lot of hype, but also some good clinical science behind it, too. I certainly prescribe fish oil a lot," said Daniel J. Rader, director of the Preventive Cardiovascular Medicine and Lipid Clinic for the University of Pennsylvania Health System.
Sales of fish oil supplements in the United States have climbed accordingly, from $35 million in 1995 to an estimated $310 million this year, according to the Nutrition Business Journal, which tracks the dietary supplement industry.
Fish oil's heart-healthy potential came to light in the early 1970s, when Danish investigators noted that despite the high-fat diet of the Greenland Inuit, they rarely had heart attacks. The Inuit diet was replete with fish containing omega-3.
Since then, the benefits of omega-3s have been studied for their role in stabilizing heart-muscle cells, thus reducing the likelihood of arrhythmia; in fighting inflammation, and making arteries more elastic.
A small study reported in the June issue of the Journal of the American Medical Association, however, raised questions about fish oil's ability to prevent irregular heart rhythms in certain high-risk patients.
Which are the best fish?
Fatty fish such as salmon, albacore tuna, bluefish, mackerel, lake trout, herring and sardines are especially good sources for the omega-3s: EPA, or eicosapentaenoic acid, and DHA, or docosahexaenoic acid.
The body can make both of them from another fatty acid, alpha-linolenic acid (ALA) - found in flaxseed, canola, olive, soy and walnut oils - but only to a limited extent.
Fish oil has been shown to improve cholesterol, lowering the "bad" and raising the "good," possibly thinning the blood and reducing blood pressure. High cholesterol and blood pressure are key risk factors for atherosclerosis, or clogged arteries, which is the major cause of heart disease.
According to the National Institutes of Health, more than 1 million people in the United States have a heart attack and 515,000 die each year, usually from arrhythmias.
Omega-3s also appear to enhance the effectiveness of statin drugs, which are prescribed to control cholesterol, so doctors often use both.
Not just for the heart.
Fish oil has anti-inflammatory properties, too, causing researchers to investigate its possible use for treating rheumatoid arthritis, menstrual cramps, ulcerative colitis and Crohn's disease, and lupus.
Other conditions for which fish oil has been found promising are asthma, cystic fibrosis and osteoporosis.
No government agency requires supplements to be tested for quality and safety, but responsible manufacturers of fish oil tablets distill impurities and contaminants out of the fish. Some fish have unsafe levels of mercury, PCBs or dioxins.
And two independent organizations - ConsumerLab.com and Consumer Reports - tested more than 57 fish oil products in 2003 and 2004 and found that all but two were fresh and contained roughly their claimed amounts of omega-3s. None were found to have significant levels of mercury, PCBs or dioxins.
'Do what you've got to do'.
This kind of information wasn't available 20 years ago, when Michael S. Vogel first tried fish oil. He was looking for ways to avoid the fate of his father, who suffered from heart disease for 10 years before dying at 52.
"Fish oil was just a fad then," Vogel said, "based on people trying things rather than scientific proof." In April, under the supervision of Rader, Vogel again began taking fish oil capsules, along with prescription statin medications, to help control his cholesterol. He also eats plenty of fruits and vegetables, and he regularly runs and plays golf. (…)
We're at the age where you've got to do what you've got to do," said Vogel, 62, an executive recruiter from Margate, N.J.
Source: Knight Ridder Newspapers
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