Toasting your bread may cause DNA damage and raise your cancer risk, says new research.
Many people like to toast their bread to a crisp for their breakfast, but health experts warn that regularly overdoing it can increase the risk of cancer.
“The darker it is, the higher their acrylamide content,” explains food toxicologist Bernd Schaefer of the German Risk Assessment Institute, referring to a chemical compound suspected of being carcinogenic.
Research has proven the carcinogenic effects of acrylamide on animals, Schaefer notes, although no scientific studies have yet been carried out on humans.
Acrylamide is released when starchy foods that also contain the amino acid asparagine are heated to high temperatures.
The compound, which builds up when temperatures exceed about 120°C, is genotoxic, meaning it causes damage to a person’s DNA.
“We cannot establish a threshold below which it is safe,” Schaefer notes, admitting that experts don’t yet know exactly how dangerous it is.
If you eat dark toast once in a while, as an exception, you do not need to worry. “But if you regularly consume high quantities of acrylamide, there may be risks,” Schaefer explains.
It’s not just dark bread that could pose a health risk. Coffee may also contain varying amounts of acrylamide depending on the extent to which beans have been roasted. However, experts believe that other substances may counter that effect.
“We suspect that coffee also contains substances that provide some sort of protection against the effects of carcinogenic substances,” Schaefer said, citing a World Health Organization (WHO) study carried out last year.
Exactly how that works remains unclear, but research has so far spared coffee from any blame for cancer.