Is Fish Oil a Waste of Time for Preventing Heart Disease?
The press has recently been absolutely covered with stories saying that it is pointless to take fish oil for heart health as a result of a recent study that was just published in the New England Journal of Medicine. Some of the headlines have been quite alarmist.
Take a look at a few of the recent headlines that came out as a result of the study:
- Forbes asked: Fish Oil Or Snake Oil? Study Questions Omega-3 Benefits, with an article that suggested that people are wasting billions of dollars a year taking supplements.
- The Huffington Post had an article asking: “Is fish oil the new snake oil”
- Fox news said that: “Omega-3 supplements don’t lower heart attack, stroke risk for some” in its article.
Given all the fuss I thought I’d try to dig into some of the science involved to see whether these claims really stand up to scrutiny.
So first let’s look at the study and some of the stronger and weaker points of it.
This was a very large study, with more than 12,000 participants. That is a pretty good sign as the bigger the study is, usually the more statistically significant it is (this is another way of saying that it is more reliable). But at the outset there are two small question marks over the study. The first is that it is funded by a drug company, in this case by Sanofi, which makes insulin injections. Now I’m not suggesting anything tricky in this, but there is a long history of drug companies sponsoring and then publishing research that they agree with and of not publishing trials or studies that produce findings that they disagree with. In this case I have no idea whether Sanofi has an interest in the outcome, but it is a small warning sign when reading a study to see it has been paid for by a pharmaceutical company (especially one that sells expensive medicines and would probably not make much money out of fish oil capsules).
The design of the study seems reasonably robust as this followed what is known as a “double blind” protocol in which participants didn’t know whether they were getting Omega 3 or a placebo (a harmless substitute) or whether they were also getting a drug, Insulin Glargine, which helps control blood sugar, as compared with the standard treatment.
The second question mark I have is over the population selected for the study. In this case the study was conduced in people suffering from diabetes or showing early signs of the disease. As Fox news notes in its report on the study:
“In the new study funded by Sanofi, which makes insulin injections, researchers examined 12,500 people who had Type 2 diabetes, impaired fasting glucose levels (based on a test of glucose levels after a period of fasting), or impaired glucose tolerance (based on a test that shows how well a person’s body can regulate glucose after drinking a glucose solution).
The participants’ average age was 64, and more than half (65 percent) were men. At the study’s start, the participants’ average daily intake of omega-3 fatty acids was 210 mg, and 60 percent of participants had already had either a stroke or heart attack, or had undergone surgery aimed at preventing one.”
This immediately tells me this the study may say many interesting things about fish oil supplements in a very ill population, but it may not say very much about its effects on a healthier population. In fact the authors of the study say as much. In trying to figure out why they found no benefit (about the same number of people died from heart attacks in the trial and placebo groups) proposed a few explanations. Among these were:
- People in the study were taking lots of other medication already, some of which may have provided some protective benefit against heart disease.
- The dose of fish oil (just under 1 gram a day) may have been too low
- The test group was already very sick and fish oil may not help in such cases
The study makes for interesting reading and can be found in full here. But before cutting out fish oil supplementation I would wait for further evidence from 3 other big trials that are currently underway. Moreover, there is also good evidence of fish oil providing a number of other benefits that are still worthwhile.
Fish oil is certainly not the coming messiah. Taking it regularly will not make us immortal any more than jogging an extra mile a day or keeping that beef jerky bag in the grocery aisle.
Because remember, fish oil supplementation is essentially that–a supplement to our otherwise supposed healthy living.
So in the end, will I continue to brave the fishy breath and ever-widening hole in my pocket? Yes.
But I will also run that extra mile and, perhaps one day, resist the jerky.
That sounds sensible to know.