Dr Justine Butler explains why fish oils are not the best choice
Like a record stuck in a groove – the advice just keeps on repeating itself. Eat more fish to be healthy, to make your brain grow, to turn you into Superman (or woman). It’s all down to the amazing powers of omega-3 fatty acids. The impression given, of course, is that this one action
can turn a rubbish diet into a healthy one.
The real problem isn’t just lack of omega 3 fats, it’s the generally appalling state of most people’s diets. Fish isn’t a popular food in the UK and seven out of 10 people don’t eat any. We really should stop looking for a quick miracle fix and focus on the bigger picture…improving our diets by cutting out foods laden with saturated animal fats, cholesterol, sugar and salt and eating more fruit, vegetables, pulses, whole grains, nuts and seeds.
It gets a bit complicated but it’s worth following. There are three types of omega 3 fatty acids. ALA (short chain fatty acids) comes from several plant sources, including flax seed oil, walnuts and soya beans and isn’t readily absorbed by the body. EPA and DHA (long chain fatty acids) are found in oily fish and are easily absorbed. But that’s only half the story – the half the media concentrates on.
Commercial fishing is devastating the world’s oceans and fish stocks are plummeting so there just isn’t enough fish for everyone even if you could persuade them to eat it. Worse than this, oily fish – all oily fish – contain neurotoxins and carcinogens as a result of humankind having polluted all the world’s oceans. That’s why the Food Standards Agency advises pregnant women, nursing mothers and children to limit the amount of oily fish they eat and to avoid some species entirely. They don’t exactly shout it out so you’ve probably never heard this caution.
What they never tell you is that the human body is quite capable of converting the short chain plant oils into the long chain oils found in fish. The bonus is, they’re not polluted with traces of deadly poisons such as dioxin, PCBs and mercury, they don’t involve slaughtering billions of animals and destroying the marine environment and they’re entirely sustainable.
The conversion process isn’t particularly efficient, but to put it into perspective, one tablespoon of flax oil is enough for the day. Of course, with a handful of walnuts, some seeds on your salad and greens on your plate you will be increasing your intake markedly.
You can even improve the rate of conversion by avoiding eggs, meat and dairy products, which will reduce your cholesterol intake, get rid of processed foods as much as possible and avoid trans-fatty acids from margarines and hydrogenated vegetable oils. Avoiding fried foods, alcohol, caffeine, sugar, smoking and stress is also helpful as is ensuring that you get a good intake of minerals, including zinc and chromium.
The latest studies show that it’s the ratio of omega 6 to omega 3 that’s important, not just how much omega 3 you eat. The optimum ratio of omega 6 to omega 3 is somewhere between 4:1 and 10:1, according to the WHO. As omega 6 tends to cancel out omega 3 in the body, you can improve your ratio of omega 3 simply by cutting back on foods containing omega 6. The easiest way is to swap sunflower, safflower and corn oils for flax, rapeseed and soya bean oils.
The real message out of all this is, for a healthy life, dump as much saturated animal fat from your diet as you can, avoid trans-fats and increase your intake of fibre and antioxidant-rich foods such as whole grains, fruit and vegetables.