Scientists have warned that a chemical released during the cooking process of several family favourite foods could raise the risk of heart attacks and strokes by 60 per cent. Called acrylamide, this substance forms when starchy foods like bread, potatoes and coffee are heated, such as during baking, frying and roasting.
It is abundant in burnt carbohydrates, such as toast, triggered by the reaction between natural sugars and heat that causes browning. Acrylamide can also be found in foods created during industrial cooking such as ultra-processed-foods, as well as in cigarettes and some cosmetics.
Concerns that acrylamide in food can trigger reactions in the body that could cause cancer have circulated for years. But now a team of Spanish experts have found another possible risk from acrylamide consumption -- cardiovascular disease. The researchers, who published their findings in the journal Nutrients, looked at dozens of studies dating back to 2007, involving over 100,000 individuals. They found higher acrylamide intake was linked to both a higher risk of suffering from serious cardiovascular medical emergencies like heart attack and stroke, as well as death from these conditions.
The researchers, from multiple universities and health bodies, referenced studies that showed extreme levels of acrylamide was linked with an 84 per cent increased risk of cardiovascular death in vulnerable people, such as those at risk of type 2 diabetes. High acrylamide exposure through diet was said to increase the risk of cardiovascular death by between a third and two-thirds. They also referenced one Chinese study that showed people at the higher levels of acrylamide exposure had between a 47 and 67 per cent increased chance of suffering from cardiovascular disease in the next decade.
Across the studies the average level of acrylamide in diet ranged from 32.6 to 57 micrograms per day, with the poorer cardiovascular outcomes observed at the more 'extreme' end of the scale. Acrylamide content in an average slice of toast is thought to be roughly 4.8 micrograms per slice, and this doubles when burnt, Professor Oliver Jones, an expert in chemistry at RMIT University in Melbourne, told The Telegraph. The Spanish scientists stated that while exactly how acrylamide damages cardiovascular health is unclear, lab tests suggested potential mechanisms.
One theory is that the substance induces fat collection in bodily tissues as well as increasing inflammation, which could contribute to pre-cursors to cardiovascular problems like obesity. They added that further research on the potential implications of acrylamide for heart health is critical given the high exposure in everyday life. 'It is a ubiquitous food processing contaminant to which the entire population is unintentionally exposed throughout life,' they wrote.
'Exposure to acrylamide comes not only from ultra-processed foods, but also from home-cooked and restaurant foods, even when using new cooking methods such as air frying. Given the above mentioned, finding ways to mitigate acrylamide production and consumption is one of the most important areas of research in the food industry.'
They said this was critical given a general lack of awareness about acrylamide among the general population. 'The population largely unaware of acrylamide production in home-cooked foods and its presence in their daily diet,' they wrote.
'Moreover, browned foods are mistakenly perceived as more appealing and flavourful.'
They added: 'The increase in the consumption of ultra-processed foods in recent decades, especially among adolescents, remains a public health concern'.
The had limitations, including that the majority of studies analysed were based in the U.S., which could limit the relevance to other groups.
Cardiovascular disease accounts for about a quarter of all deaths in UK, equivalent to 170,000 deaths a year or 480 each day. Acrylamide intake has been linked to an increased risk of cancer . While this danger has mostly been observed in animal studies, involving high amounts of acrylamide, experts agree the potential risk extends to people and we should aim to reduce the amount we consume as a result. However some scientists dispute the quality of the evidence.
According to Sir David Spiegelhalter, Professor of statistics at Cambridge University, a person would need to consume 160 burnt slices of toast per day for it to have a worrying effect . Regardless, health authorities like the NHS have published advice on how people can reduce their acrylamide exposure. These include aiming for only a 'golden yellow colour' when baking, toasting, roasting or frying starchy foods rather than a brown.
They also recommend following packet instructions when cooking products like chips at home and avoiding over-cooking them for extra browning. Health authorities also highlight general dietary advice to eat plenty of fresh fruit and vegetables and to favour healthier cooking methods like boiling or steaming will also reduce acrylamide exposure. Acrylamide risk assessments published by UK regulators have failed to determine, based on current evidence, exactly how much a person's cancer risk increases from consuming it.