A report by the International Agency for Research on Cancer (IARC) has found that processed meats increase the risk of cancer and that red meats are "probably carcinogenic". The IARC is the World Health Organization's cancer-specific agency.

Processed meats are meats that have undergone "salting, curing, fermentation, smoking, or other processes to enhance flavour or improve preservation" and includes hot dogs, sausages and bacon. Red meat includes beef, pork and lamb.

The IARC said there was "sufficient evidence" that eating processed meat causes colorectal cancer and it has been classified as carcinogenic to humans – 50g of processed meats a day increased the risk of colorectal cancer by 18%. They said that red meat does have "nutritional value" but the findings support recommendations to limit the amount of meat we eat.

The dangers of increasing red meat intake have been previously highlighted in documentaries such as Forks Before Knives, which espoused plant-based diets, though the WHO ruling does not go that far, saying instead that red meat is only "probably carcinogenic to humans" based on "limited evidence". The report considered over 800 studies when coming to their conclusion.

"For an individual, the risk of developing colorectal cancer because of their consumption of processed meat remains small, but this risk increases with the amount of meat consumed," says Dr Kurt Straif of the IARC.

Processed meats are now in the same carcinogenic classification as smoking and asbestos, but the IARC emphasised that it does not mean they are equally dangerous. According to estimates by the Global Burden of Disease Project around 34,000 deaths a year worldwide are attributable to diets high in processed meats.