The $2.3 billion a year Omega-3 supplement industry has been telling us for decades that their products, made largely from industrially reduced fish, can do everything from protecting against heart attacks to alleviating depression, and guarding against type two diabetes.
Scientific studies have been poking holes in the heart health claims for years, and now a fresh takedown from the UK’s University Of East Anglia has come right out and said that these supps also have no impact on anxiety or depression.
At RSNG we’re all about scientific fact over marketing hype, so we’ve investigated the latest news to bring you this FAQ breakdown…
So, what does this latest study say?
Basically, that the game is up for taking fish oil tablets to fight anxiety or depression. The UEA Medical School study, published in the Journal Of Psychiatry looked at 31 randomised trials of 41,500 adults with and without depression and anxiety, who consumed more long-chain omega-3 fats (fish oils) (or maintain their usual intake) for at least six months.
They found that the supplements had little or no effect in preventing depression or anxiety symptoms.
Dr Katherine Deane, from UEA’s School of Health Sciences, says: ‘Oily fish can be a very nutritious food as part of a balanced diet. But we found that there is no demonstrable value in people taking omega-3 oil supplements for the prevention or treatment of depression and anxiety.’
What about a healthy heart? I heard Omega-3 supps were supposed to be good for that too?
Yeah that claim is looking more and more shaky. Last year, a Cochrane review (the international gold-standard for high quality, trusted health information) of 79 studies involving 112.059 people found that Omega-3 supps provided little or no benefit to heart health.
The UEA lead that study too and lead author Dr Lee Hooper said: ‘The findings of this review go against the popular belief that long-chain Omega-3 supplements, including fish oils, protect the heart.’
‘One in four kilograms of fish caught at any time, anywhere in the world is turned into fish meal and fish oil’
OK, but you can get Omega-3 from more places than fish oil tablets – what about those?
True – if you look at oily fish, no one is saying it isn’t a healthy food (it provides a rich source of protein boosted with Vit D, iron and selenium, for fewer calories than meat, for example), but the scientists say it’s unclear whether they provide any heart or cardiovascular health benefits.
The Cochrane review did find some evidence that ALA (the Omega-3 found in plant oils such as rapeseed or canola oil and walnuts) might give slight heart protection, but the effect is so small that one thousand people would need to increase their ALA intake to prevent one person dying of coronary disease or having a coronary episode.
So where did the idea that fish oil would even be healthy for the heart come from?
A 1970’s study of Inuit people living in Greenland found that public health records logged lower rates of cardiovascular disease. They also saw that their diet of seafood, and their blood, were high in Omega-3s, and assumed there was a link, but causation has never been proven.
Of course, 1970’s Greenland’s lack of McDonalds drive-throughs or booze-stuffed corner shops, and its abundance of reasons to go outside (like having to hunt your own food) could have also been a link, but you can’t really market a hunter-gatherer Arctic wilderness lifestyle to city dwellers, can you?
It’s all starting to found a bit fishy – why are my local drug store’s shelves groaning with these supps?
There’s a massive marine animal reduction industry that was first established during the Industrial Revolution, first to turn whales into lamp oil, but then also to combat a Vitamin D deficiency in Northern Europe that lead to the disease rickets, using cod liver oil.
Ever since, the most profitable, elite part of this industry (which also turns fish into food to feed farmed fish, and for other industrial purposes) has been fish oil for human consumption, marketed as health supps.
Wait, how were Omega-3 supps supposed to relate to mental health again?
As awareness of mental health has risen, scientists have studied the effects of food on the brain started to look for evidence that Omega-3s have anti-inflammatory effects, which could impact depression and other mental illnesses. Now, after the evidence has stacked up in many randomised trials this theory appears to have been disproven.
Where has all of this fish oil come from?
One in four kilograms of fish caught at any time, anywhere in the world is turned into fish meal and fish oil (and used in agriculture or industry, including Omega-3 supps). This is a total of between 20 million and 25 million tonnes a year.
The traditional target (once the industry moved on from whales) is small oily fish like sardines, but it has recently moved into harvesting Antarctic krill, claiming that the Omega-3 in krill is more ‘bio-available’. Of course, this takes food from whales, squid and birds and impacts the entire, delicately balanced Southern Ocean ecosystem.
Scientists believe krill have declined by 80% since the 1970s, most likely due to global warming. This is ironic, given that Krill act as a carbon dioxide sink by eating carbon-rich food near the surface and then excreting it in the depths of the ocean (as part of world’s largest animal migration, which happens daily).
‘Considering the impact of industrial fishing and plastic pollution it seems unhelpful to swallow fish oil tablets that give no benefit’
That sounds like a lot of fish to take out of the oceans to turn into expensive tablets that probably don’t even work?
Yup, and it’s doubtful that the oceans currently hold enough fish to even put them on our plates sustainably. Back in 2006 scientists looked at the rate that wild fish were being taken out of the ocean and mapped the trends forward – they showed that all seafood will run out by 2048. Just last year, the United Nations reported that 90% of global fish stocks are in the red; fully exploited, overexploited, or flat out gone.
If you do want to include oily fish in your diet, then make sure it is rated sustainable by the Marine Conservation Society and swerve fish like tuna and salmon in favour of handline-caught fish like North East Atlantic mackerel.
As UEA’s Dr Katherine Deane puts it: ‘Considering the environmental concerns about industrial fishing and the impact it is having on fish stocks and plastic pollution in the oceans, it seems unhelpful to continue to swallow fish oil tablets that give no benefit.’
WHAT NEXT? Want a scientifically proven way to improve your mood? The University of East Anglia did another study looking evidence from 290 million people and found that people who live near, or spend time outside in green spaces had lower levels of the stress hormone cortisol in their saliva. Greenspace exposure also reduces the risk of cardiovascular disease and premature death. So, get outside and spend some time in some leafy places!
Comments are for information only and should not replace medical care or recommendations. Please check with your Doctor before embarking on exercise or nutrition regimes for the first time.
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