Hidden danger - trans fats in foods

CHOICE finds some manufacturers still sneak unhealthy trans fats into our foods.
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  • Updated:26 Jun 2009

01 .Trans Australia

Fat map of Australia

In brief

  • Many of the foods CHOICE tested in 2005 still contain unacceptably high levels of trans fats.
  • There’s no real need for food manufacturers to use these heart-stopping fats. Some manufacturers have cut back, while others have stopped using trans fats altogether.

They rarely rate a mention on the label, but the trans fats hidden in many processed foods are worse for your health than saturated fats. In 2005, CHOICE tested more than 50 processed foods and found many contained trans fats at unacceptably high levels. We’ve retested and can reveal that, while the fast-food chains have reduced their levels of trans fats, and some of the foods we tested previously have eliminated trans fats altogether, others now contain even more than before. Foods such as pies, cakes and doughnuts may contain trans fats without you even knowing about it.

In 2005, CHOICE called for Australian regulations to require manufacturers to include the amount of trans fat as well as saturated fat on the label, as happens now in the US and Canada. We are still waiting.

The previous federal government set up the National Collaboration on Trans Fats with the aim of reducing the amount of trans fats in the Australian food supply, but manufacturers are still not required to identify the amount of trans fats in their products. In the US, the use of trans fats in foods has decreased 50% since labelling was introduced.

Please note: this information was current as of June 2009 but is still a useful guide today.

Global restrictions

While trans fats are not completely banned anywhere, some jurisdictions have imposed tighter restrictions on their use than in Australia.

  • Denmark (in 2003) and Switzerland (in 2008) have banned the sale of food products in which trans fats are more than 2% of the total fat.
    UK regulations require hydrogenated fats to be identified in the ingredients list on the label. But in the European Union (which includes Denmark and the UK), labels don’t have to disclose the level of trans fats unless the manufacturer is making a nutrition claim.
  • Since 1 January 2006 food manufacturers in the US have been required to list trans fats on the nutrition label immediately under saturated fat. New York and Philadelphia have banned restaurants and fast-food outlets from serving foods containing more than 0.5g of trans fats per serving; California has legislation in place that bans the use of industrial trans fats in restaurants and fast-food outlets from 1 January 2010, and bakers who make doughnuts will have until 2011 to comply. These actions have had a substantial impact on the use of trans fats in the US. (The food giant Kraft, for example, reduced the trans fat content in about 650 of its products to meet the labelling deadline.)
  • Canada also requires food labels to show the level of trans fats. In June 2007, Health Canada put the Canadian food industry on notice to limit the trans fat content of its products within two years. It set the limits at 2% of total fat for margarine and cooking oils and 5% of total fat for all other foods, including ingredients sold to restaurants. To ensure progress, Health Canada has been analysing a wide variety of foods and publishing the results.

What CHOICE wants

We want it made mandatory that the amount of trans fat and saturated fat be included on the label. We believe the national regulator, Food Standards Australia New Zealand (FSANZ) is too complacent about the well-established risks to health from trans fats; our test results clearly show its kid-glove approach isn’t working. Labelling has had a substantial impact on the levels of trans fats in processed foods in the US and Canada; there’s no reason to believe it wouldn’t have a similar impact here. But it’s also important we don’t see trans fats reduced at the expense of increased levels of saturated fats in some foods.

FSANZ claims its ultimate goal is “a safe food supply and well-informed consumers”. Trans fats offer no nutritional benefits and CHOICE believes consumers should be informed about how to avoid them.


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What are trans fats?

Trans fats are found mainly in deep-fried fast foods and processed foods made with margarine or shortening. They’re created by hydrogenation, a process that’s been used by the food industry for about 100 years, in which liquid oils rich in polyunsaturated fats are converted into more solid (and more saturated) fats suitable for making cakes and pastries.

Trans fats are also formed in the process of refining polyunsaturated oils, and some cooking oils used by fast-food outlets and bakeries for deep frying are also partially hydrogenated to slow the process of oxidation that can turn the oil rancid.

Advances in food technology, however, have made it possible for manufacturers to produce cooking oils, margarines and shortenings without depending so much on hydrogenation. There are now no valid technical reasons for manufacturers to continue using hydrogenated fats and oils.

Some foods, mainly beef, lamb and dairy products, contain naturally occurring trans fats. These fats are produced by micro-organisms in the rumen (or fore-stomach) of cattle and sheep, which partially hydrogenate the fats and oils from the animals’ feed. A recent survey found that on average about 60% of trans fats in the Australian diet come from these natural sources.

What are the risks?

Trans fats increase your risk of heart disease and sudden death from heart-related causes.

Like saturated fats, trans fats can raise total blood cholesterol levels, as well as the LDL, or “bad” component, of blood cholesterol. But they’re worse than saturated fats in that they can also lower the “good” HDL component. There’s also some evidence that these fats may increase your risk of developing diabetes.

Experts agree that, gram for gram, the risks from trans fats are greater than from saturated. In fact, the evidence against trans fats is so strong that

  • Denmark and Switzerland have banned the sale of foods in which trans fat is more than 2% of the total fat content.
  • In Australia, the National Heart Foundation Tick program limits trans fats to less than 0.2% of fat for all products except margarine-type spreads and vegetable oils which must limit trans fat to less than 1% of total fat.
  • The World Health Organization (WHO) recommends trans fats contribute less than 1% of our daily energy intake – less than 2.3g of fat for someone with an average daily energy intake of 8700kJ – and some experts now recommend complete or near-complete avoidance of industrially produced trans fats to avoid adverse heath effects.

The risk from naturally produced trans fats compared with industrially produced ones is less clear. There are chemical differences between the two, and some recent research seems to suggest naturally occurring trans fats are not as harmful – but experts still disagree on the issue.

03.What CHOICE found


CHOICE retested most of the 17 food products that when tested in 2005 wouldn’t have been permitted in Denmark or Switzerland because of their trans fat content. We also tested some new foods, namely deep-fried fast foods and doughnuts from chains as well as independent cake shops.

Where trans fats are still lurking

Of the 32 foods we analysed, these 13 contained more than 4% trans fats (as a percentage of total fat). They’re listed from highest to lowest in trans fat.

  • Coles Bakery Fresh Donut
  • Burns & Ricker Bagel Crisps Plain
  • Herbert Adams Mixed Vegetable Pasty
  • Pampas Short Crust Pastry
  • Four’N Twenty Traditional Meat Pie
  • McDonald’s McCafé Iced Donut
  • Independent bakery Doughnut
  • Donut King Glazed Donut King Iced Classic
  • Sara Lee Snack Quiche Lorraine
  • Sargents Party Pack Sausage Rolls
  • Mr Donut Choc Ring Doughnut
  • Woolworths Caramel Slice (According to the nutrition information panel, this contains less than 0.1% trans fats, but our testing found 0.7%, 4% of total fat content. A second retested sample showed the same result. Woolworths told us the manufacturer hadn’t changed the process or ingredients but they were considering changing the label to <1% trans fats.)

Burns & Ricker Bagel Crisps now contain a greater percentage of trans fats than in 2005.

What's improved?

Foods with trans fatsTwo of the original 17 products, both of them fast foods, have made significant reductions, and four have almost eliminated trans fats altogether. They’re listed below with their current percentages of trans fats as a percentage of total fat.

  • Nutella Hazelnut Spread (<0.4%)
  • McDonald’s McNuggets and medium fries (<0.7%)
  • Erica’s Kitchen Vol au Vents (0.5%)
  • Ritz Cheese Crackers (0.9%)
  • McDonald’s Big Mac and medium fries (2% – just within the Danish/Swiss limit)
  • Hungry Jack’s Whopper and medium fries (2.4% – just over the limit but a big improvement on their 22.5% we found in 2005).

Unfortunately, however, according to their labels Hungry Jack’s have at the same time increased their level of saturated fat in the same meal from 36% to 54%. Even though gram for gram, trans fats are worse for the heart, foods that contain a lot more saturated fats could negate any benefit from cutting back on trans fats.


Doughnuts are deep-fried, so most of their fat comes from the cooking oil. CHOICE tested doughnuts from 12 different outlets – seven of the doughnuts were obviously cooked in partially hydrogenated oils as they contained more than 4% trans as a percentage of total fats, but the other five were cooked in oils low in trans fats.

Our findings (see the table, below) show that food manufacturers can use low-trans cooking fats and oils if they really want.

The power of naming and shaming is also clear. In 2008, Krispy Kreme came under attack in the NSW state parliament and from the media for continuing to use trans fats in Australia while eliminating them from their US products. As a result, Krispy Kreme switched to a low-trans cooking oil from February this year. In the first sample of Krispy Kreme doughnuts we tested (bought in early March 2009) a massive 29% of the fats were trans fats, but a second sample, bought a month later, contained only a tenth as much trans fat.

And we nearly had a heart attack on the spot when we saw how much fat overall some of these doughnuts contain. Dreamy Donuts Glazed and the second sample of Krispy Kreme doughnuts contained a massive 27%-28%, and three others were over 20%.

Doughnuts (ranked by % trans fat)
Trans fats (% of total fat)
Total fat (%)
Krispy Kreme Glazed Original (March 2009)
29.4 20.1
Coles Bakery Fresh Six Pack Iced Donuts
23.1 7.8
McDonalds McCafe Iced Donut
6.3 20.8
Donut King Glazed Donuts
4.9 20.3
Donut King Iced Classic
4.8 12.6
Independent A Iced doughnut
4.6 13.1
Mr Donut Two Pack (A)
4.4 13.5
Krispy Kreme Glazed Original (April 2009)
2.9 27.4
Dreamy Donuts Glazed
0.4 27.9
Woolworths Bakehouse Donut Iced Six Pack
<1.4 7
Independent D Iced doughnut
<0.9 11.2
Independent C Iced doughnut
<0.7 13.7
Independent B Iced doughnut
<0.6 17.3

Table notes

(A) Mr Donut told us that, according to their own testing, their cooking oil contains no more than 0.4% trans fats.

Trans fats Our lab measured the amount of each individual fatty acid. This figure is all trans fats combined as a percentage of total fat.

Total fat The percentage found by our lab from one sample of each type of doughnut bought from supermarkets, doughnut chains and independent cake shops in Melbourne. The amount of fat absorbed would depend on cooking conditions so there is likely to be some batch-to-batch variation.

04.What's being done?


Food Standards Australia New Zealand

Although Australia’s regulator, Food Standards Australia New Zealand (FSANZ) wants to see industrially produced trans fats removed from the food supply, it’s not in favour of requiring trans fats to be labelled. FSANZ argues, based on a survey of consumer responses in the US (carried out in 2003, before labelling was introduced), that introducing trans fat labelling in Australia would have only a very small effect on consumption of trans fats. It further argues we shouldn’t rely on the approach taken in other countries, but take into account the fact that dietary intakes here are already low by international standards.

However, CHOICE isn’t convinced.

FSANZ estimates that on average Australians eat 1.4g of trans fats per day, which is well below both the WHO’s recommended maximum daily intake and below the average daily intake of trans fats in the US, Canada and Europe. However, averages can be deceptive. FSANZ’s statistics also reveal that more than a million Australians are currently putting their health at risk by eating more than the WHO’s recommended maximum.

Processed foods that make claims such as “low cholesterol” or “high in polyunsaturates“ are already required to state the level of trans fats on the label. Most cooking oils and margarine-type spreads fall into this category and give a breakdown of their fat composition. It’s an indication of how effective labelling can be that of the dozens of such products on supermarket shelves we found only two containing more than about 1% of the total fat as trans – You’ll Love Coles Vegetable Oil with 4.6% and You’ll Love Coles Sunflower Oil with 1.8%. 

What are manufacturers doing about trans fats?

According to FSANZ, the industry seems ready to and capable of responding to market demand for lower trans fats in foods, claiming all the manufacturers it contacted plan to reduce trans fats levels in their products. CHOICE had a more mixed response.

  • Patties Foods (Herbert Adams and Four'N Twenty) told us they don’t normally test for trans fats, but do use low levels of trans fats in some of their products, and are working with the National Heart Foundation towards healthier products.
  • McDonald’s introduced a vegetable oil blend in November 2006 that contains less than 1% trans fat. A spokesperson said they continue to look for opportunities to improve the nutrition profile of their menu.
  • Burns and Ricker Bagel Crisps’ importer told us they are working with their US supplier to reduce the amount of trans fat to the previous low level.
  • Sara Lee said they are working with their suppliers to seek alternative fats low in trans but which don’t compromise the quality of their products.
  • Krispy Kreme said they aim to introduce a low trans and low saturated fat product by the end of 2009.

Suitable margarines and cooking oils low in trans fats are now available, and there’s no evidence that changing to these fats affects the quality, cost or availability of food. Food manufacturers and fast-food outlets could change their practices if there were more incentive for them to do so.