Medics refute claims on well-done meat
Medical experts have dismissed claims that new research proves that eating overcooked meat is twice as likely to cause cancer than previously thought.
The claims were made in national newspapers, including the Daily Mail and the Daily Express, following the publication of a study carried out by researchers from the Norwegian Institute of Public Health and the German Institute of Human Nutrition, which was funded by the Norwegian Research Council.
In the study, the researchers bred four types of mice: normal mice, mice that were genetically modified to produce a human enzyme called sulphotransferases (hSULT mice); mice that were genetically predisposed to developing tumors (Min mice) and mice that were genetically predisposed to developing tumours and produce human sulphotransferases (Min/hSULT mice).
The mice were treated with PhIP, a compound that is formed when meat and fish are fried or grilled at high temperatures and scientists recorded the both the presence of tumours and tumour size. The results indicated that the incidence of colon cancer was 31% in Min mice, compared to 80% in Min/hSULT mice.
Researchers concluded that this demonstrated that “normal laboratory mice are not a good model for assessing the health risk to humans following ingestion of food mutagens from well-done meat and fish”.
The national media interpreted the study to mean that overcooked or burnt meat could increase the risk of cancer more than previously thought.
However, the NHS Choices website said: “It is not clear how relevant the findings are for human health, especially as PhIP did not lead to tumour development in healthy mice that produced human sulphotransferases but were not genetically susceptible to tumours.”
It added that large cohort studies, which follow people up for a long period, would give the best evidence for the effects of PhIP on humans, and pointed out that “at least two published cohort studies have shown that methods of cooking meat do not affect the risk of lung or prostate cancer”.