One of the most worrying aspects of the western diet today is not so much the amount of fat, but the type of fat it contains. We have long been warned about the risks from diets high in saturated fats, but in fact, the trans fats found in many processed foods are a far worse problem.
What Are Trans Fats?
Trans fats are by-products of ‘hydrogenation’ – a process by which liquid vegetable oils are chemically altered to turn them into more solid fats, which are used by the food industry instead of more expensive animal fats. They are artificial, warped and ‘twisted’ versions of natural polyunsaturated fats (such as omega-6 and omega-3).
In addition to being cheap, trans fats add bulk to products, have a neutral flavour and give products a long shelf life. However, they have no nutritional value whatsoever. Instead, these fats are toxic.
Why Are Trans Fats Bad For You?
Trans fats have long been known to increase the risks for many serious degenerative physical health conditions. Higher dietary intakes of trans fats are linked with:
- Higher blood cholesterol levels, and an increased risk of heart attack and stroke
- Insulin resistance and Type 2 diabetes
The effects of trans fats on mental health and performance are likely to be even more serious. The brain is 60% fat – and trans fats compete with the natural (untwisted) omega-3 and omega-6 fatty acids that we all need for healthy brain development and function.
Research in this area is still limited, but higher intakes of trans fats have already been linked with increased risks for
Which Foods Contain Trans Fats?
Hydrogenated vegetable oils (which contain trans fats) are still used in all kinds of processed foods – including crisps and snacks, cakes, biscuits, pastries, sauces, soups, salad dressings and many more. They are also found in numerous take-away foods and ready-meals, but there is no way for the consumer to know this. (See Stender et al 2006 whose study found huge variation in exactly the same 'fast food' meals bought at different outlets)
In the UK, there is no specific requirement for the trans fat content of products to be included on food labelling, although some manufacturers have started to do so voluntarily. If a product contains any ‘hydrogenated’ fats, it may contain trans fats. Look out for the words ‘partially hydrogenated’ on food labels - because these products almost always contain some trans fats.
Why are Trans Fats Still Allowed in our Food Supply?
This is a very good question.
The UK Faculty of Public Health and Royal Society for Public Health recently proposed that consumption of trans fatty acids (TFAs) should be virtually eliminated in the United Kingdom by next year. Their report noted that, “it has been proven that industrially-produced TFA can damage health,” “there is no known safe level of consumption,” and “banning TFA from foods is a relatively easy way to help protect the public.” (See Mozaffarian and Stampfer, 2010).
Government regulation (i.e. banning these dangerous fats – or at least restricting them to an absolute minimum, as Denmark has already done) would virtually eliminate these toxic substances. New York decided to ban trans fats some years ago (see Okie et al 2007) and since then, other countries have been following the lead first set by Denmark. The NHS watchdog NICE, recommended a ban on trans fats in 2010.
However, the UK government is still relying on ‘voluntary’ action by the food industry. This ensures that trans fats will still be used by many food manufacturers and catering outlets (either through ignorance, or simply to increase their profits) – so consumers will continue to find them very difficult to avoid.
‘Voluntary’ action fails to protect the public (and particularly the most vulnerable members of our society). See The Food Programme – Trans Fats and Dying for a burger? Why are trans fats still legal in the UK?
For further information, see:
TFX (The Campaign to Ban Trans Fats in Food)
Fats And Cholesterol – Harvard School of Public Health