Rashers of bacon and ham are on the list of processed meats now thought to be as carcinogenic as tobacco.
The shock findings come from a report by the World Health Organisation (WHO).
It is expected to list processed meat as a cancer-causing substance, while fresh red meat is also expected to be regarded as bad for health, it is reported in the Daily Mail.
The classifications, by the WHO’s International Agency for Research on Cancer, are believed to regard processed meat as “carcinogenic to humans”, the highest of five possible rankings, shared with alcohol, asbestos, arsenic and cigarettes.
The World Cancer Research Fund (WCRF) has warned for several years that there is “strong evidence” that consuming a lot of red meat can cause bowel cancer.
It also says there is “strong evidence” that processed meats – even in smaller quantities – increase cancer risk.
One possible reason is that the compound that gives red meat its colour, haem, may damage the lining of the bowel.
In addition, when meat is preserved by smoking, curing or salting, or by adding preservatives, cancer-causing substances (carcinogens) can be formed.
Studies also show that people who eat a lot of red meat tend to eat fewer plant-based foods that protect against cancer.
The WCRF advises that people can reduce their bowel cancer risk by eating no more than 500g (cooked weight) per week of red meat, such as beef, pork and lamb.
It also says people should eat processed meats such as ham, bacon and salami as little as possible.
Foods like hamburgers, minced beef, pork chops and roast lamb are also regarded as red meat.
As a rough guide, the WCRF says 500g of cooked red meat is the same as 700g of raw red meat.
Processed meat is meat which has been preserved by smoking, curing or salting, or by the addition of preservatives.
Examples include ham, bacon, pastrami and salami, as well as hot dogs and some sausages.