As It Happens

Those fish oil supplements probably aren't protecting you from heart disease, research finds

Lee Hooper led a review that looked at dozens of trails on the benefits of omega-3 supplements on heart health.

'The magic pills don't seem that magic these days,' said the lead author of new review

A new report says omega-3 supplements aren't doing much to benefit heart health. (iStock)

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Many people take them on a regular basis, but a new report says omega-3 supplements aren't doing much to benefit heart health. 

Lee Hooper studies research synthesis, nutrition and hydration at the University of East Anglia Norwich Medical School in England. She led the review that was published this week by Cochrane, an organization that does systematic reviews.

Hooper spoke with As It Happens host Laura Lynch about her review of dozens of randomized control trials.

Here is part of their conversation. 

Are people who are buying fish oil supplements wasting their money?

Well, some of them, maybe.

If you are prescribed fish oil supplements by your doctor, then you will be given them for good reason — so you may be prescribed them to bring your triglyceride levels down, for example.

But aside from a doctor telling you to take them, is there any other reason?

If you decided you want to buy omega-3 capsules yourself because you think it will reduce your risk of heart problems, we've got very large amounts of evidence now that suggest that actually there will be no useful effect of that on your heart or on risk of things like stroke.

Researchers reviewed dozens of studies on fish oil supplements and heart health. (CBC)

How common is it in your knowledge for people to take these supplements for exactly that — to improve their heart health?

It's hard to tell. I don't think we've got any very good evidence.

We know, for example, that in the United States more EPA/DHA, those are the omega-3 fats, more ... comes from supplements than it does from actual fish. So, there are large quantities being taken by people. But it's hard to know why people have chosen to take those supplements.

The so-called long-chain omega-3 supplements, like what is found in oily fish, isn't beneficial. But what about different types of omega-3s, such as those that can be found in nuts? Is there any benefit there?

ALA is the other type of omega-3. As you say, it's found in canola oil, which we also call rapeseed oil, and some nuts including walnuts for example.

That shows some, but quite small, amounts of benefit to coronary heart disease. It does look as though having a little bit more of that ALA from those sources will be quite a beneficial thing to do. But ... you only get a small amount of benefit from it.

On the other hand, it's fairly easy to have a little bit more rapeseed [or] canola oil. You can add a little bit into salad dressings, add a little bit into cooking, and you get that benefit ... with very little difficulty.

Tell me how you did your review.

We looked for all the randomized controlled trials that had gone for at least a year … that had randomized people either to taking omega-3 in some form or not taking that.

We found 79 trials. There's a huge number of trials out there, and those trials included well over 112,000 people in trials for at least a year — some of them up to eight years.

We have a huge amount of information that we're basing this on. If there were effects on our heart, if there were effects on stroke, we would be seeing those in a group this large.

But we're not seeing effects, and we're consistently not seeing effects.

It really does suggest that we're not getting benefits from those long-chain omega-3s, the fish-based omega-3 supplements.

What we don't have is very much evidence on the effects of eating oily fish. We looked for those studies too. We only found four trials that looked at the health effects of eating oily fish, and sadly we don't have enough information from those trials to know very clearly whether we are seeing health benefits on the heart from eating more oily fish itself.

Lee Hooper led a review that looked at dozens of trails on the benefits of omega-3 supplements on heart health. (University of East Anglia Norwich Medical School )

Do you take any supplements yourself?

No I don't. I try and eat well.

That sounds like not bad advice ... especially after hearing about this.

To look after our hearts, there are lots of really positive things we can do, aren't there?

I mean staying fit and active is great. Not smoking is a sensible thing to do. If we drink alcohol, drinking it in moderation only makes sense.

And eating, I mean there are so many wonderful foods out there to eat, aren't there, that are just great and healthy.

And don't rely on a magic pill.

The magic pills don't seem that magic these days. So, let's go back to basics. We know what works.

Written and produced by Katie Geleff. Q&A has been edited for length and clarity.

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