Could one of our favourite roast veggies be a cancer risk?

There is nothing like a nice hot roast dinner in winter. Whether you’re a big meat eater and enjoy the tender lamb with thick gravy or are vegetarian/vegan who enjoys the crispy roast vegetables, there is no denying that a roast dinner is an iconic and much loved meal of ours. But how would you feel to know that one of the tastiest vegetables on the plate may now be considered a cancer risk? That’s right, it’s those crispy, golden brown potatoes that could be a problem. The UK Food Standards Agency (FSA) has warned that cooking potatoes at high temperatures could be linked to cancer.

Roasted potatoes. Image source: Flickr

A chemical called acrylamide is responsible for this new health claim. Acrylamide can form in starch-heavy foods such as bread and potatoes when they are cooked or processed. So, how does this chemical form in our food? Well, acrylamide is formed during a process called the Maillard reaction which is the browning of cooked foods that occurs when an amino acid, such as asparagine (which is found in a variety of potatoes), reacts with sugars in the presence of heat, converting the asparagine into acrylamide. This reaction usually occurs at temperatures over 120 degrees Celsius and to make our spuds crispy and brown we usually bake them at about 180 degrees Celsius; enough heat for acrylamide to form. I don’t want to alarm you but this chemical can also occur in cereals, toast, biscuits and horrifyingly enough, even in coffee…

Browning of toast is an example of the Maillard reaction. Image source: Flickr


So this all sound very… chemical, but do we have a reason to be alarmed? Possibly. Acrylamide, when in the body, converts into another chemical called glycidamide which can attach to our DNA and create mutations. Laboratory studies have found that acrylamide does cause different cancers in rats and mice, and while there is no direct evidence of acrylamide causing cancer in humans, it is still something we should be concerned about. Emma Shields from Cancer Research UK believes that while it is difficult to study acrylamide effects in the human body, there’s no reason it can’t affect our DNA the way it affects an animals DNA. Although it is a health concern and something we should be aware of, Shields argues that there are many other cancer-causing lifestyle choices that are more prominent and concerning, including smoking and obesity.

Acrylamide is naturally occurring so it will also be present in our foods but there are a number of actions we can take to ensure we don’t consume too much acrylamide. Firstly is the obvious one: eat a balanced, healthy diet. There is no surprise that processed foods such as chips and biscuits are full of chemicals including acrylamide, so eating a balanced diet will mean less acrylamide and an overall healthier lifestyle. Secondly, don’t cook starchy foods, like potatoes and root vegetables at high temperatures for too long. Even though crispy, brown potatoes are divine, cooking them until they are yellow/lightly golden may be the healthier option (golden spuds are better than no spuds at all if you ask me).

There are a few other ways to reduce acrylamide concentrations in your potatoes. Food Standards Australia and New Zealand (FSANZ) recommends that they be stored in a cool, dark place (above 6 degrees Celsius) and not in the fridge as the process of ‘cold sweetening’ will occur, causing an increase in chemicals, triggering the production of acrylamide when they are cooked. Also, consider boiling, steaming or microwaving as a way to heat, as these methods do not seem to produce as much acrylamide as frying or baking.

Currently work is being done with industries in an attempt to reduce the levels of acrylamide in food. There are a number of options including different processing techniques, lowered cooking temperatures and the use of enzymes to prevent acrylamide forming. This is all positive but for some foods, reducing acrylamide may alter the taste too much. So, for now, the best we can do is ensure we have a healthy balanced diet that isn’t always full of overly brown potatoes…

This youtube clip provides a short and succinct summary of acrylamide and how it affects our food:

4 Responses to “Could one of our favourite roast veggies be a cancer risk?”

  1. Murraya Lane says:

    You’re right James! Apparently it is occurring in a lot of our foods which is quite concerning! There seems to be new information coming up all the time about foods being linked to cancer and other illnesses.. hopefully this one doesn’t become a huge concern..
    I definitely agree with you Isaac! it seems every day there is something new that can cause cancer… scientists do seem to be pedantic, with constant links being drawn however with the amount of chemicals and additives in processed foods these days, there could be so many health risks that are yet to surface. I think you’re right when you say that non-expert readers can misinterpret findings. Often when someone reads the word risk, they immediately catastrophise.
    Great point Nastasia, it definitely does occur in the chocolate making process but I don’t know if FSA has looked into it or not. The FDA (food and drug administration) has definitely identified that acrylamide is present in many chocolate drinks and cakes

  2. James Spyrou says:

    Terrifying! I remember reading about the Maillard reaction only recently, and I believe it also occurs when roasting meat. Hopefully the levels of acrylamide commonly seen in cooked foods aren’t liable to cause humans any significant risk.

  3. Hockey says:

    Great read Murraya! I just ate roast potato 🙁
    I have hitherto avoided known carcinogens as I do not wish to welcome cancer into my body, however modern science seems to suggest that almost everything is carcinogenic! No smoking, no red meat, no broccoli, no sunlight, no mobile phones, no rubber…

    As scientists are we being pedantic in ‘suggesting’ that consuming these products can cause cancer? Smoking, for example, exposes our body to known toxins, so there is greater cause-and-effect in the manifestation of cancer than what is being suggested of acrylamide from animal studies. I suppose scientists are obligated to disseminate their knowledge, but the non-expert reader may misinterpret the findings, so that an item, like a mobile, becomes known as a cancer-causing agent rather than merely a ‘potential risk’.

  4. Nastasia Bartlett says:

    I think the Maillard reaction also occurs in the chocolate making process when the cacao beans are roasted, oh no! Do you know if the FSA have looked into chocolate as a carcinogen?