New research suggests that eating everyday foods such as crisps and bread could lead to certain types of cancer.
Here, we look at food types that are linked with cancer – and find out if they are best avoided.
CRISPS, CHIPS, BISCUITS AND BREAD
New research shows prolonged high intakes of acrylamide – a chemical found in baked, fried and grilled foods such as crisps, chips, bread, biscuits, crackers, and breakfast cereals – could cause nerve damage, and, according to animal studies, affect male fertility and trigger cancer.
A recent Swedish study is the first to suggest that acrylamide is formed when carbohydrate-rich foods such as potatoes, rice and cereals are fried or baked (acrylamide was not formed when the foods were boiled).
In fact, researchers found that a bag of crisps may contain up to 500 times more acrylamide than the World Health Organisation allows as a maximum safety limit in drinking water. Some fries from fast-food chains were said to contain up to 100 times more.
It is impossible to avoid acrylamide because it’s found in so many everyday foods – and not just fatty crisps and fries. Foods that we feed to the whole family such as crispbreads, cereals and wholemeal bread are all tarred with the acrylamide brush.
The Food Standards Agency (FSA) says it is too early to advise people to change their diets or the way they prepare food, stressing only that diets rich in fruit and vegetables are known to protect against some forms of cancer.
However, dietitians say we should not ban all these foods from our diet just yet.
Catherine Collins, chief dietician of London’s St George’s Hospital, says: ‘Our bodies have been exposed to low levels of acrylamides for decades and our estimated daily intake is 1,000 times lower than the amounts found to affect rats.’
‘If you have a healthy defence system, your body recognises toxins such as acrylamides and will stop them from causing damage to your cells,’ she says.
Collins insists these are early studies and says we should not stop eating bread or cereals which contain high levels of vitamins and minerals – important for building up immunity.
However, she says, reducing your intake of fried and fatty foods is recommended, although the odd packet of crisps or chips won’t harm you.
A consistently high alcohol intake is linked to an increased risk of cancer of the mouth, oesophagus, bowel, liver and breast. In fact, an American study which followed the lifestyles of more than 200,000 women for 14 years found that for postmenopausal women, less than a drink a day was related to a 30 per cent increase in death from breast cancer, compared to non drinkers.
The recommended daily allowances for alcohol are set at three to four units for men and two to three units for women (a unit is a pint of beer, small glass of wine or pub measure of spirits), and above these limits there is a continuing risk to health.
People who eat large amounts of red meat (pork, beef and lamb), and barbecued and processed meat, such as sausages, bacon and hamburgers are at a higher risk of bowel cancer, according to a report in the British Medical Journal.
The potential culprits are heterocyclic amines which are formed on the surface of meat when it’s grilled, roasted, fried or barbecued – especially when burned or charred.
Although animal studies suggest that high intakes of heterocyclic amines can promote cancer, there is no direct evidence in humans. In 1998, the Department of Health advised that we should not exceed an average of 140g (5oz) of red and processed meat a day.
A high salt diet has been linked to an increased risk of stomach cancer. It is thought the salt, in foods like bacon and processed meals, can damage and inflame the soft lining of our stomach, leaving us vunerable to cancer-causing tumours. Fortunately, this type of cancer has decreased since refrigeration replaced more traditional preserving methods, such as pickling and salting.
Improved treatment of Helicobacter pylori infection, a condition that inflames the stomach lining, has also helped. About three quarters of the salt we eat comes from processed foods, especially smoked, canned, pickled items, sauces, fast-food and ready meals.
The Department of Health advises cutting back to no more than 6g a day – which is about half of what we currently eat – to reduce the risk of high blood pressure and stroke. The World Cancer Research Fund says this may also help reduce our stomach cancer risk.
PEANUTS AND GRAINS
Found on peanuts and grains, aflatoxins are a type of fungus that increases the risk of liver cancer. They are chemicals produced by moulds found in foods such as nuts, cereals, and spices, especially in tropical countries.
The EU has set safety limits for aflatoxin content of imported foods, but since it is not visible, contaminated produce occasionally slips through the net. However, the FSA considers that consumption of a very small amount of aflatoxin on a single occasion is unlikely to have cancer-causing effects.
Dr David Phillips of The Institute of Cancer Research says: ‘Peanuts sold within Europe and America are safe because there are strict regulations,’ he says.
‘The best advice to tourists travelling elsewhere is to avoid peanuts that look mouldy. The problem
is most likely to be in areas of the world where peanuts
and grains are grown or stored in humid conditions. We know
that this is the case in regions of China and West Africa,’ he says