Fish oil has long been touted as a reliable means of reducing coronary artery disease (CAD). Chances are you regularly take a fish oil supplement capsule. Possibly your doctor even suggested it to you. Perhaps you regularly eat oily fish as part of a heart healthy regimen.
Sit up and take notice, then. The praise for the beneficial effects of fish oil may be much ado about nothing.
Wait, what blasphemy is this? It’s the conclusion of a study published in the Canadian Journal of Cardiology in April 2014.
In 2013, scientists set out, in part, to determine “whether there was ever reliable evidence to support the hypothesis that the Eskimo diet provides CAD protection.” Oh, snap.
The Original Study: Lots of Fish Means a Heart-Healthy Life
In 1968, a Danish researcher, Dr. Jorn Dyerberg, was intrigued by something he saw in the Danish Medical Society’s weekly journal. The item indicated that Greenland’s Inuit people somehow experienced significantly less CAD than other populations. Dyerberg wanted to know why.
He and another researcher, H.O. Bang, went to Greenland five times to study the Inuit. They determined that the high-fish, low vegetable diet of the Inuit was responsible for their lower incidence of CAD.
Based on that finding, the billion dollar fish oil industry was born. United States, Canadian and European medical organizations recommended frequent fish in the diet, particularly oil-rich salmon. They still do. All the buzz is aimed at one thing — keeping heart disease at bay.
There’s just one little problem. The original study didn’t really prove any of that, says the newly released report.
Flawed Research: It’s “Very Soft” and “Only Speculation”
“I reviewed this original paper and it turned out to be that they actually never measured the frequency of heart disease in [Inuit],” Dr. George Fodor, the study’s lead scientist, told the CBC News.
“They relied upon some [public health records] in Greenland, and also relied on hearsay. People told them that [heart disease] was very rare,” he added. “So this is very soft, from the point of view of science.”
The new study took a hard look at exactly what science backs up the original suppositions. The research team came away unimpressed.
“The alleged absence of CAD in Greenland Eskimos is a paradoxical finding, given that this is a population mainly sustained on a diet high in animal fat, absence of fruits and vegetables and other important nutrients,” the study said. “In other words, [it is] a diet which violates all principles of balanced and heart-healthy nutrition.”
So it would seem. As Fodor’s team discovered, it looks like the original researchers focused on state-provided data that told them only 12 percent of the Inuit died from CAD. Unfortunately, 20 percent or so of the death certificates in those cases were of questionable value because they weren’t completed by a doctor or had other problems.
“Considering the dismal health status of Eskimos, it is remarkable that instead of labeling their diet as dangerous to health, a hypothesis has been construed that dietary intake of marine fats prevents CAD and reduces atherosclerotic burden,ö the scientists concluded.
Ultimately, says Dr. Fodor’s team, Dyerberg and Bang’s research “focused on the dietary habits of Eskimos and offered only speculation that the high intake of marine fats exerted a protective effect on coronary arteries.”
The Danes never actually examined the cardiovascular status of the Inuit they were studying. They made inferences based on what now appears to be flawed information, according to Fodor’s research. Others who later cited the original study didn’t look past the conclusions or cast a critical eye on them. Quite the opposite occurred.
Fodor’s research reveals that the Inuit actually experience about the same level of CAD as everyone else does. In addition, they’re somewhat more susceptible to strokes and apparently have a high risk of heart disease. Go figure.
The new study concludes the Inuits’ “overall mortality is twice as high as that of non-Eskimo populations and their life expectancy is approximately 10 years shorter than the Danish population.”
Wondering Whether to Throw Out Your Fish Oil Capsules?
“Most of the researchers never read [the original 1970s] papers. They just took it at face value that what they said is so,” Fodor told the CBC News.á”The fish oil capsules I don’t think will stand up to a critical review. They simply don’t do anything for you. The people should know that it doesn’t help to prevent heart disease.”
So now you’re wondering what to do with those pricey fish oil supplements and all that frozen salmon in your freezer, right? Maybe you’re feeling a little confused? Ask your doctor about this study during your next annual physical.
Now that the original underpinnings supporting the fish oil industry have been challenged, you never know how much the medical world’s opinion might change. Or not. It’ll be interesting to see what happens from here.
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