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For a while now, we’ve been told to avoid saturated fats and increase polyunsaturated fats (particularly omega-3) to protect ourselves against the long term risk of heart disease. But a new study finds that there is no advantage to using supplements. So should we just stop taking them?
You might have seen the news headlines recently such as:
BBC: Fish oil supplements for healthy heart ‘nonsense’
The Independent: Omega-3: Fish oil supplements do nothing to prevent heart attacks or stroke, major study finds
The Mail: Taking Omega 3 supplements WON’T cut the risk of early death and may even do some harm, major study finds
The Sun: It’s oil a myth
These are just a small selection, many more newspapers and online news sites had similar headlines, but where did this come from and can we believe it?
We’ve been told that replacing saturated fats with more polyunsaturated fats is heart protective – so does this now mean we should dump our supplements?
Before we look at the research, let’s look at what omega-3 actually is.
There are a number of ways we get omega-3 supplements over-the-counter:
- Cod liver oil capsules
- Fish oil capsules
- Krill oil capsules
- Vegan algae oil capsules
We may be taking these for a number of reasons, and not just heart health – and we’ll look at the different benefits of omega-3 in just a moment, but first – what exactly is it?
Omega-3 in a nutshell
When we think of fat, most of us may think of that white solid mass that accumulates when cooking meat or the white streaks on top of bacon. But actually, there is no one single type of fat.
Fat can be loosely categorised into two main groups: saturated fat and unsaturated fat. Omega-3 falls into the group of unsaturated fat.
But it gets more complicated than that, unsaturated fats are further split into mono-unsaturated fats and polyunsaturated fats. These types of fats (or oils) are liquid at room temperature and are commonly associated with plant oils (although animal fat also has these groups too).
Omega-3 itself falls into polyunsaturated fat, but moreover – it is considered an essential fat! Why? Because our body has very limited capacity to make it, and therefore we must get it from our diet.
Whether we supplement or not, we must get essential fats into our diet.
Why is Omega-3 particularly important?
Now that we’ve established that omega-3 is both a polyunsaturated fat and an essential fat, we also need to know that it often comes along with its cousin, omega-6. Omega-6 is much more prevalent in our diet – it’s much more easily obtained.
But, unfortunately, omega-3 is not! So we have a situation in the modern world where people get far more omega-6 in their diet than omega-3!
To complicate matters, there is no one type of omega-3, there are three types:
- alpha-linolenic acid (ALA)
- eicosapentaenoic acid (EPA)
- docosahexaenoic acid (DHA)
ALA is found mainly in plant oils such as flaxseed, soya bean, and rapeseed (Canola) oils. DHA and EPA are found in fish, other seafood and algae.
Now you might remember that I said it’s essential because the body has limited capacity to make omega-3. Actually, it cannot make ALA at all! It can only make EPA and DHA, and it cannot make DHA unless there is an adequate supply of EPA!
So you might think that it’s important to supplement on ALA so that you body can make EPA and in turn, DHA. Actually, no! It’s better just to get EPA and DHA from your diet, because our bodies just aren’t efficient at making these fats.
And, we’re unsure just how much ALA gets absorbed anyway.
We need DHA for good eye health, male fertility, our brains need DHA – every cell in the body depends on omega-3. Omega-3 is important for a robust immune system, and has been shown to help reduce inflammation in chronic disorders such as rheumatoid arthritis.
The UK recommendations for omega-3 are set out in the table below – where the recommendation is two portions per week. Also, below are the UK government recommendations on where we should be getting omega-3.
|Age||One portion size|
|18 months to three
|¼ – ¾ small fillet or
|four to six years||½ – 1 small fillet or
2 – 4 tablespoons
|seven to eleven
|1 – 1 ½ small fillets
or 3 – 5 tablespoons
|12 years to adult||140g (5 oz) fresh fish
or 1 small can oily.
|Source: British Dietetic Association|
The best sources of omega-3 are considered to be oily fish, such as mackerel, salmon, pilchards, trout, sprats, whitebait, sardines and herring.
But fish, in my mind, is not the best way to get omega-3. And I’m only using two reasons for this. First, it’s just not sustainable (4)! There is so much illegal fishing (5) going on in the world that the sea’s resources of fish will inevitably deplete.
Secondly, we’re pumping so much bad stuff (6) into the sea that it’s polluting the waters and the animals that live in it.
You have all heard about the plastics problem in the sea! We still don’t know how much plastic has accumulated in sea animals and what impact that has on human health once consumed.
Note about supplements
If you care about your health and the environment, you’d move from ocean-based omega-3 supplements to microalgae
Most supplements are ocean-based; of all, krill oil is the most controversial since krill live around the Antarctic and are a major food source for marine wildlife and aquatic birds. Stripping out krill for oil denies food for a huge range of animals, potentially contributing to their decline in numbers
Cod liver oil is high in vitamins A and D – sounds good, just as long as you’re not overdosing by popping a multivitamin along side it.
Fish oil (from sustainable sources) is probably the best supplement, but only if supplied in its triglyceride form – as fish oil may not get absorbed and could just end up coming out as it went in.
Algae oil is great for vegans, but it’s low in EPA – which is has the most anti-inflammatory benefits. For sustainability, microalgae reigns! New technologies are improving its EPA content, and it is the most bioavailable (7).
Now let’s go back to the headline and look at the research that kicked off this debate.
These headlines are reporting on the research done at the University of East Anglia, United Kingdom. It was published by the Cochrane Library, considered by many as the gold standard for systematic reviews.
A systematic review of randomised controlled trials is at the top of the research pyramid, meaning that its stringent and methodical practice of reviewing clinical trials is the preferred reading material for those making policy changes.
This review looked at 79 randomised controlled trials that lasted at least 12 months, which in total included just over 112,000 participants. The reviewers used a meta-analysis to pool together all the results to identify whether there was a significant effect of using supplements against a control (typically a placebo).
They found that there was no significant benefit in supplementation with EPA/DHA and only a small benefit with ALA.
The problem with looking at studies that just compare heart health outcomes with a supplement are many-fold – but the most important thing to consider is, would the outcome be different if compared supplements usage with eating omega-3 in its natural state (ie food)?
Of course, the other issue is that we don’t know a lot about the participants’ lifestyles: do they have good diets? Exercise? Have low stress? Sleep well? All of which can influence our propensity to heart disease and strokes.
We do know that the researchers included participants who have a history of cardiovascular diseases as well as those that didn’t; people of elderly ages; smokers; people with hypertension (high blood pressure); diabetics; people with Alzheimer’s or other chronic diseases.
I have to question whether we can seriously expect omega-3 to protect against heart disease and stroke if there are so many other risk factors it has to fight?
What other influencing factors are there that we don’t know about – for example, were the groups taking supplements and the control on isocaloric diets (were they taking in the same amount of calories from all the macronutrients)?
The study contained a very low number of exclusion criteria – I would like to think the studies included were as similar as possible, not just in terms of the supplement, but the populations being studied.
Of course, if they all followed immaculate lifestyles, and no one had a coronary event – could you attribute that to the omega-3 or the lifestyle? Nutrition research is fun huh!
The reality is, it doesn’t really doesn’t matter whether you get every essential vitamin, mineral and nutrient through supplements if you don’t exercise, are over-stressed, don’t sleep well, and eat a terrible diet or eat a lot of calories. If our lifestyle is poor, taking no amount of supplements will compensate.
At least, I’ve yet to see evidence that it does.
This does not detract from the importance of this study however, because it’s going to be the best we’ll get in terms of looking at omega-3 and heart health – we just need to keep in mind that any study looking at nutrition will be fraught with limitations.
The fact remains, omega-3 is important for so much more than just heart health; we cannot just take a supplement, ignoring the rest of our lifestyle, and expect that supplement to be the elixir for health – life, unfortunately, just isn’t like that.
Image by Pixabay – StevePB
Seb is a writer and blogger of food and nutrition. He holds a bachelors and a masters degree in nutrition science, and has studied sports and exercise nutrition at postgraduate level. He specialises in plant-based nutrition and believes passionately that we can all live with a little less meat. He writes for www.veggieandspice.com and www.itsaboutnutrition.com