Roast potatoes, burnt toast and cancer: your essential Good Health survival guide

Yes, the claims are terrifying — but don’t panic: Our experts tell you what you REALLY need to know to enjoy your favourite foods...SAFELY

MilliONS will have been choking on their breakfasts with the news yesterday that well-done roast potatoes and burnt toast could raise the risk of cancer. The Food Standards Agency (FSA) has advised people to cut down on these kinds of over-cooked starchy foods.

‘What we’re saying is that if you get served a piece of toast like that, do not panic and do not think to yourself: “i must not eat that,” ’ says dr Guy Poppy, chief scientific adviser to the FSA.

‘What we are saying, though, is that if you want to have toast every day, to reduce the amount of exposure you’ll get, you’re better off eating toast of a light golden colour, rather than dark brown.’

But as the mail has revealed today, it’s not just potatoes and toast that could be risky: a host of other foods are also implicated — from gingerbread to crispbread, instant coffee and crisps made with potato or ‘trendy’ veg.

So, how DO you protect yourself from these apparently harmful foods — and does this mean the end of the traditional Sunday roast?

WHY CAN’T I HAVE CRISPY FOOD?

THE worry is acrylamide — a chemical considered so toxic that in drinking water, just 0.1 micrograms per litre is allowed, 100 times less than the amount of arsenic allowed.

This is to protect consumers against acrylamides used in industry (where it’s used to make dyes and plastics).

The chemical is also found in food such as burnt toast and roast potatoes and any others that naturally contain an amino acid called asparagine as well as carbohydrates: acrylamide is produced when these foods are heated to above 120c.

This includes root vegetables, wheat, rye and soy. Crisps and chips have been found to contain high levels of acrylamide; pizza, toast and biscuits are also on the danger list.

The World Health Organisation has said the levels of acrylamide in food pose a ‘major concern’.

But unlike with water, there is no legal maximum.

HOW CAN I TELL IF I’M EATING ACRYLAMIDES?

‘ACrylAmidE, an odourless white crystal compound, does not exist in raw uncooked foods,’ says Simon Cotton, senior lecturer in chemistry at the University of Birmingham.

levels in food depend on cooking time and method: roasting, grilling, frying and toasting can get food much hotter than 120c, so can produce higher levels of acrylamide.

‘Any foods that contain asparagines and carbohydrates together and have been heated to high temperatures will contain this chemical in differing amounts,’ says dr Cotton.

‘The higher the temperature and the longer you heat food, the higher the levels of acryalmide,’ says Peter Wilde, professor of food science at the institute of Food research.

A clue to a high acrylamide content is the colour — for example cooked potatoes that are dark yellow, brown or black — but also its texture: how hard and brittle it is.

‘This explains why fresh bread contains less acrylamide than crispbread, which is heated until they are baked completely dry,’ says Professor Wilde. ‘Gingerbread men are baked until they are very dry and browned, which is why this type of biscuit has a higher concentration of acrylamides than softer shortbread.’

Acrylamide is also found in coffee — the beans contain asparagine and carbohydrates — which has been roasted for long periods in high temperatures.

Worryingly, researchers from Poland in a study published in 2013 that analysed 42 samples of coffee, found instant coffee contains 100 per cent more acryalmide than fresh roasted, citing differences in manufacturing.

I LIKE MY TOAST DARK BROWN, NOT BURNT

‘FOOd does not need to be blackened and charred to contain this toxin,’ says dr Cotton. ‘The browning process alone can cause acrylamide to be created. This is a sign that the surface area has reached the required temperature to cause the chemical reaction to make acrylamide.’

Scraping the top layer off toast will remove acrylamides on the surface. But there’s no need to be obsessive.

The occasional bit is not going to do you any harm,’ says Professor Wilde. ‘But it’s also wise to think about the cumulative effect in your diet.’

BUT HOW HARMFUL IS ACRYLAMIDE?

ACrylAmidE is not yet proven to be a carcinogen in humans.

‘The evidence that acrylamide is potentially carcinogenic to humans comes from studies in rodents,’ says dr Teresa Norat, a research fellow from the School of Public Health at imperial College london.

‘This is because it is very difficult to accurately assess a person’s usual intake of acrylamide from foods.’

Studies have not shown any increased risk between eating acrylamides and 16 different types of cancer (including bowel, stomach, ovarian, breast and prostate). ‘However, there is modest evidence of a potential effect on the risk of endometrial, kidney and ovarian cancer,’ says dr Norat.

‘We don’t really know what constitutes a hazard over a lifetime’s exposure,’ says dr Cotton. ‘But the amounts needed to produce cancer in the rodents tested are believed to be 1,000 to 10,000 times the normal levels of exposure in humans.’

However, high levels of acrylamide in the workplace have been shown to cause neurological symptoms such as muscle weakness and could potentially damage nerve cells in the brain.

IS MICROWAVING OR BOILING BETTER?

miCrOWAviNG food has been found to produce less acrylamide than frying, baking or roasting.

‘This could be because temperatures in microwaves can be controlled while cooking under a grill or over an open flame is less predictable,’ says dr Cotton.

‘100c (the boiling point of water) does not get the food hot enough to cause the chemical reaction so you will not find a significant amount of acrylamide in boiled food.’

WHAT CAN I DO TO PROTECT MYSELF?

‘SOmE manufacturers are looking into changing the variety of potato they use to make frozen chips because

some contain more asparagine than others,’ says Professor Wilde.

Pre-soaking chips before cooking can also reduce levels.

The coffee industry has been researching reducing the level of acrylamide in roast coffee by storing it for longer so the chemical degrades. However, this also seems to impact on freshness.

The FSA campaign Go For Gold recommends cooking food until is yellow, not brown or black.

‘Blanch potatoes before frying as this removes some asparagine,’ says dietitian Priya Tew.

DO I HAVE TO GIVE UP THE ROASTIES?

IT’S the surface area that is exposed to heat that is the potential source of acrylamides, so one bigger potato is better than two little ones, says Catherine Collins, a dietitian and spokesperson for the British Dietetic Association. ‘And have thicker chips rather than French fries, as they have a smaller surface area per serving.

‘The same applies, for example, to cake. If you are worried about acrylamide, you could have a slice of cake rather than muffin, which has a bigger exposed surface.’.

Sugar and asparagine (both needed for acrylamide production) are water soluble — so soak potatoes in water before roasting.

‘About half an hour should do it,’ says Don Mottram, emeritus professor of food chemistry at Reading University.

‘This will then reduce the acrylamide made during cooking.’ And parboil potatoes before roasting so they don’t need such intense cooking to get soft all the way through.

Changing the way you cook could also help. Research published in 2006 found that baking crisps made of rye and wholewheat at lower temperatures for longer made less acrylamide than if you blasted them at a higher temperature for a shorter time.

And don’t use old potatoes that have been hanging around.

‘The longer a potato is stored the more of the starch turns into sugar and, therefore, the more acrylamide is likely to be produced when they are cooked,’ says Professor Mottram.

‘All potatoes will have been stored for some time, but you can avoid keeping them for too long. When they look old and wrinkled, throw them out.’

ARE CHILDREN AT MORE RISK?

CHIlDRen have a lower body weight so, potentially, they could ingest more acrylamide in relation to their volume.

However, there are no studies on the effect on children. But there’s evidence that babies in the womb can be harmed by their mothers’ eating habits, including acrylamide-rich food.

Acrylamide, unlike many other toxins, can pass through the placenta and was found in the foetal blood, too. ‘This makes it very worrying since early development in the womb is critical to health in later life,’ says Professor John Wright, clinical epidemiologist and a leading researcher in this field.

IS IT AS HARMFUL AS SMOKING?

‘We CAn’T compare acrylamide and smoking since so many questions still need to be answered,’ says Professor Wright.

‘The evidence linking acrylamide to cancer is still disputed and is not strong enough to draw comparisons to risk factors we already know about.’

Dr Cotton says it is a question of weighing up the risks. ‘look at your diet, look at your circumstances and decide for yourself.

‘Are you a smoker? In which case you are already absorbing high levels of this chemical, so you should keep dietary levels to a minimum. As far as we can see, there is a small risk associated with eating browned, starchy food, but balance is everything.’

Catherine Collins adds: ‘Coffee is a source of acrylamides, but may also be cancer protective.’

The thing to remember is that the compound has probably been in our food since Man first started roasting food over open fires and so it seems that we have been living with some levels in our diet for millennia.