Cheap and vital – why omega-3 helps you live longer

Telegraph

03-03-2025

From reducing your risk of heart disease and staving off dementia to easing joint pain, omega-3 – typically found in oily fish such as salmon and sardines – is often said to have huge health benefits. The latest research to spotlight the power of omega-3 is the Do-Health clinical trial which set out to establish how we can extend our 'healthspan' (our healthy active life). Do-Health recruited more than 2,000 healthy people over 70 from five European countries and measured the impact of various interventions. It had already found that a daily omega-3 supplement reduced participants' rate of infection by 13 per cent and falls by 10 per cent. This month, in a new paper, the research team also concluded that those taking omega-3 for three years had aged three months less than others on the trial, as measured by biological markers
According to Prof Parveen Yaqoob, an expert in omega-3 and professor of nutritional physiology at Reading University, our interest in these fatty acids stretches back to the 1950s, when researchers travelled to Greenland to study the Inuit diet. 'They ate huge amounts of whale and seal meat which was extremely rich in omega-3, and the first observation was that the Inuits had a very long bleeding time if they cut their skin,' says Prof Yaqoob. 'It suggested they had quite thin blood. The second observation was that even though whale and seal meat was really high in fat, the presence of cardiovascular disease was really low.' Somehow, this fatty diet was not causing the obesity-related chronic diseases we see here.
Despite much evidence of benefit, there is still no recommended intake, and available supplements have wildly different concentrations. NHS guidelines suggest eating two pieces of fish a week, one of which should be oily fish (rich in omega-3). 'Unfortunately, 70 per cent of people in the UK eat no oily fish at all,' says Prof Yaqoob. So what are we missing? And how much do we need?
What is omega-3?
'They are a particularly unusual family of fatty acids,' says Prof Yaqoob. 'The three main omega-3s are ALA, DHA and EPA, and it's widely believed – though not conclusive – that DHA is more important for brain function, while EPA plays a greater role in cardiovascular health. You really only find EPA and DHA in oily fish.'
We need a balance of fats in our diet, and humans evolved on the edges of land masses, eating fish, but the switch to agriculture has meant our diet now contains far more omega-6 fats (which come from vegetable oils). 'The ideal omega-6 to omega-3 ratio should be 3:1,' says Nicola Shubrook, a nutritionist with Urban Wellness. 'Some estimates suggest most people in the UK have a ratio of between 10:1 and even 50:1.'
Signs you're deficient in omega-3
'It's vital for the grey matter in your brain – every cell in your body has omega-3 in its membrane,' says Geoff Mullan, the chief medical officer at Human People, a longevity specialist healthcare provider. It can play a role in the regulation of blood clotting and also our inflammatory responses. 'That makes it important for the heart, skin, brain, joints and pretty much every system in the body.' The signs are:
Dry, brittle skin – rough skin (keratosis pilaris) around the upper arms is a common early sign
Dry eyes
Joint pain – stiffness and slow recovery after exercise
Low mood
What are the other four health benefits of omega-3?
Cardiovascular: reduces risk of clotting, lowers triglycerides (a type of blood fat)
Reduces inflammation – may improve many inflammation-related conditions, including rheumatoid arthritis, eczema, psoriasis and dry eye disease
Improves mood and cognitive function
Reduces all cause mortality
Omega-3: Benefits for women's health
Pregnancy and breast feeding
EPA and DHA omega-3s are critical to the development of the foetal brain and retina. This is why infant formula – and breast feeding supplements – contain DHA
PMS
There's evidence that omega-3 can ease some of the psychiatric symptoms such as depression, anxiety and lack of concentration.
Which are the best omega-3-rich foods?
'Eating whole foods rather than supplements is always going to be better because of all the other nutrients that come with it,' says Nicola Shubrook, a nutritionist with Urban Wellness. 'A piece of salmon doesn't just contain omega-3; it has vitamins and minerals, all that protein, the amino acids.' Oily fish are the best – in some cases, the only omega-3-rich foods. These are the fish that store fat all over their body.
How much you need to eat is a grey area. The participants in the Do-Health trial were taking omega-3 supplements of 1g per day. So how much oily fish equates to this?
100g mackerel = 5.5g of omega-3 (five-and-a-half 1g supplements)
100g salmon = 4g of omega-3 (four 1g supplements)
100g sardines = 3g of omega-3
100g of anchovies = 2.1g of omega-3
100g kippers = 1.4g of omega-3
Cod liver oil
White fish store fat in their liver – not their flesh – so cod liver oil is another source. 'The generations that grew up taking cod liver oil absolutely swear that it has a beneficial effect, especially on keeping their joints supple,' says Prof Yaqoob.
One tablespoon (14g) = 1.7g of omega-3.
Vegetarian sources
ALA is found in dark green vegetables, walnuts, flaxseed, chia seeds, hempseed and soybeans – all of which are packed with other nutrients too. However, they are not a useful source of EPA or DHA, which the human body needs. 'Humans can only convert 5 to 10 per cent of these, so it's a bit naughty of the food industry to say, 'Get your O3 eating flaxseeds. Actually, you can't,' says Mullan.
The only vegetarian source is vegetarian omega-3 supplements which are derived from algae. 'It's really a nice way to get it,' says Mullan. 'Fish don't make O3 either. They eat it from plankton and then store it. The algae supplements are a step farther back, so you're not risking contaminants. You avoid the fishy taste too.'
Who shouldn't take omega-3?
Anyone on blood thinners should speak to their doctor before taking an omega-3 supplement.
FAQs
How much omega-3 should I take a day?
Unfortunately, there is no agreed answer. The NHS simply advises eating one meal of oily fish a week, although the American Heart Association advises on eating two, and adds in a 1g daily supplement for heart disease patients. The Institute for Functional Medicine (IFM) recommends higher therapeutic doses (2-4g of O3 a day) to improve inflammation and autoimmune conditions, while the European Food Safety Authority (EFSA) recommends daily supplements that have a breakdown of 250mg of EPA+DHA for general health, and a higher dose 2-4g/day for triglyceride reduction.
Does omega-3 reduce belly fat?
There are lots of reasons for belly fat, and O3 is no magic solution, but it can play a role in mitigating some of the harms by reducing levels of inflammation and harmful free radicals. Levels of omega-3 tend to be lower in overweight people.
Is omega-3 good for the skin?
Yes! 'It's very strongly anti-inflammatory, it helps maintain a healthy skin barrier and helps with keratin production,' says Mullan. It can regulate oil production, improve hydration, soothe irritation and improve skin conditions such as eczema, acne, rosacea, psoriasis and keratosis pilaris.