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Old habits -

If you are in the habit of scraping the burnt bits off your toast, it’s probably because your parents taught you to do so when you were a kid.

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Verging on the superstitious -

Indeed, we all have eating habits that we learnt from our parents, some so lacking in reason that they may be deemed superstition.

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The truth about burnt food -

When it comes to removing burnt bits of food, however, your parents may well have been on to something.

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Acrylamide -

In 2002, scientists at the University of Stockholm discovered that when we heat certain foods, including potatoes, bread, and biscuits, to more than 120°C, a substance called acrylamide forms.

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Dangerous to humans -

Acrylamide is thought to be dangerous to humans in a number of ways. Firstly, and scientists are certain of this, acrylamide is neurotoxic to humans.

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Neurotoxicity -

This means that consuming acrylamide can negatively affect the nervous system, although scientists are not exactly sure how or why.

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Theories -

There are theories that acrylamide may attack the structural proteins within nerve cells, or that it may inhibit the anti-inflammatory systems that protect the nerve cells from damage.

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Link with neurodegenerative disease -

There is also evidence from animal studies that suggests long-term exposure to acrylamide in the diet can increase the risk of neurodegenerative disease, such as dementia.

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Neurodevelopmental disorders -

Dietary acrylamide may also be associated with neurodevelopmental disorders in children, according to assistant professor Federica Laguzzi at the Karolinska Institute, Sweden.

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Neurodevelopmental disorders -

Laguzzi has found a link between higher acrylamide intake in pregnant women and an increased risk of low birth weight, head circumference, and length of newborn babies.

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Potential link to cancer -

Perhaps the most talked about repercussion of eating burnt food, however, is an increased risk of cancer.

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Potential link to cancer -

Indeed, your parents may have told you to scrape off those burnt bits of toast because they have carcinogenic properties.

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Acrylamide in animals -

While scientists are certain that acrylamide can be carcinogenic in animals, this is only in doses much higher than would ever be found in human food.

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No conclusive evidence - When it comes to the carcinogenic effects of acrylamide on humans, researchers have not yet been able to come to a definitive conclusion.

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Official stance -

According to the European Food Safety Authority, acrylamide could increase the risk of humans developing cancer, particularly in children.

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Probable human carcinogen -

After 30 years of being classified as a "probable human carcinogen," however, there is still inconsistent evidence that acrylamide causes cancer in humans.

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Dutch study -

There was one study in the Netherlands that found a higher risk of endometrial and ovarian cancers in women with a higher exposure to acrylamide.

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Dutch study - The same researchers also found a slight association between a higher acrylamide intake and an increased risk of kidney cancer.

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Lack of other evidence -

These findings are yet to be confirmed by any other researchers, however, and it is not yet clear whether what the Dutch scientists found was correct.

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WHO's opinion -

In 2010, the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives suggested that more long-term studies are needed before we can draw any conclusions about the link between acrylamide and cancer.

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Nevertheless -

That said, they nonetheless supported efforts to reduce acrylamide levels in food. As a result, key players in the food industry are taking measures to reduce acrylamide in our food.

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Acrylamide in wheat production -

At one end of the supply chain, resources are being deployed to help farmers reduce the potential for acrylamide to form in products made from wheat.

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Acrylamide in wheat production -

Asparagine, the substance that turns into acrylamide when heated, is found in plants, and wheat grain in particular accumulates much more asparagine than is necessary.

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Gene editing -

Wheat grain also appears to accumulate even more asparagine when it does not get all the nutrients it needs; a process that researchers are trying to stop using a gene editing technique.

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Role of food producers -

At the other end of the supply chain, certain food producers have been able to reduce the levels of acrylamide in their products with quite some success.

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Case study - The Dutch breakfast cake ontbijtkoek, for example, now only contains around 20% of the acrylamide it used to.

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Reducing acrylamide when cooking -

According to Fatima Saleh, associate professor of medical laboratory sciences at Beirut Arab University in Lebanon, there are also ways to reduce acrylamide levels when cooking at home.

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Case in point -

When making fries, for example, soaking the cut potatoes in hot water for 10 minutes can reduce their acrylamide formation by as much as 90%.

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Looking ahead -

There is a long way to go in the quest to understand the exact relationship between acrylamide intake and cancer risk.

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All in all -

With increased scientific interest, however, we will eventually get there, and in the meantime it may be an idea to avoid those burnt sausages wherever possible.

Sources: (BBC) (Runner's World)

See also: Foods you should never eat raw

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