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Warning over 'burnt toast chemical' acrylamide's cancer risk

Monday 23 January 2017

"Browned toast and potatoes are 'potential cancer risk', say food scientists," BBC News reports.

The Food Standards Agency (FSA) has launched a campaign about the possible health risk of acrylamide, a chemical formed when starchy foods are subjected to a high temperature.

The campaign is called Go for Gold – a reference to the advice that when frying, baking, toasting or roasting starchy foods like potatoes, you should aim for a golden yellow colour (or lighter).

What are the risks associated with acrylamide?

Acrylamide is a chemical compound naturally produced when foods high in starch are fried or baked at high temperatures. It can be found in potatoes, chips, crisps, bread, and other cereal and wheat products.

There is evidence rodents exposed to high levels of acrylamide develop cancer, as we discussed back in 2012 about a study looking at frozen chips.

It is currently unclear whether a similar risk exists in human. It's possible prolonged exposure to acrylamide through eating acrylamide-rich food for many years could increase the risk.

Acrylamide is currently defined by the World Health Organization as "probably carcinogenic to humans".

This means while no definitive proof has been found that acrylamide is carcinogenic, as a precaution, exposure to acrylamide should ideally be limited to as little as possible.

What advice does the FSA provide?

The FSA offer the following four tips:

  • go for gold – as a general rule of thumb, aim for a golden yellow colour or lighter when frying, baking, toasting or roasting starchy foods like potatoes, root vegetables and bread.
  • check the pack – check for cooking instructions on the pack and follow them carefully when frying or oven-cooking packaged food products such as chips, roast potatoes and parsnips. The on-pack instructions are designed to cook the product correctly. This ensures that you aren't cooking starchy foods for too long or at temperatures that are too high.
  • eat a varied and balanced diet – while we can't completely avoid risks like acrylamide in food, eating a varied, balanced and healthy diet will help reduce your risk of cancer. Get more advice on eating a balanced diet.
  • don't keep raw potatoes in the fridge – don't store raw potatoes in the fridge if you intend to cook them at high temperatures (such as roasting or frying). Storing raw potatoes in the fridge may lead to the formation of more free sugars in the potatoes, a process sometimes referred to as "cold sweetening", and can increase overall acrylamide levels, especially if the potatoes are then fried, roasted or baked. Raw potatoes should ideally be stored in a dark, cool place at temperatures above 6C.

What are the FSA and the food industry doing to help?

The FSA reports it is working with the food industry to identify and implement measures to reduce acrylamide levels in food.

Examples include:

  • selecting potato varieties with low levels of reducing sugars that are suitable for baking, roasting or frying
  • bread manufacturers reducing the time and temperature during baking to avoid excessive browning of the crust 

How has the campaign been received?

It is fair to say that the response to the campaign has been mixed.

Cancer Research UK agreed that "eating fewer high calorie foods like crisps, chips and biscuits, which are the major sources of acrylamide" would be of benefit, while also pointing out that the link between acrylamide and cancer in humans is currently neither clear nor consistent.

And some commentators have accused the FSA of "nanny statism". John O'Connell, chief executive of the TaxPayers' Alliance, is quoted by The Sun as saying: "Barely a day goes by without a public health decree from the army of nanny statists funded by taxpayers.

"The FSA doesn't even know if this chemical is bad for us, yet it sees fit to tell us how to cook our chips just in case."

Steve Wearne, director of policy at the FSA, responded to these criticisms by saying: "We are not saying people should worry about the occasional meal… this is about managing risk over a lifetime.

"Anything you can do to reduce your exposure will reduce your lifetime risk. People might, for example, think 'I like my roast potatoes crispy', but they will just decide to have them less often."

Should I be worried?

The occasional slice of burnt toast isn't going to kill you, and the link between acrylamide and cancer in humans is unproven.

But as Cancer Research UK rightly points out, a diet consisting of mainly calorie-rich starchy foods, whether or not there is any specific link to cancer, should be avoided on general health grounds.

Of course, avoiding acrylamide all together will do you little good if you indulge in activities definitively known to increase cancer risk, such as:

You can reduce your cancer risk by: