Bacon, ham and red meat fans are significantly more likely to develop bowel cancer than people who only eat them occasionally, the largest UK study of its kind has found.
People who eat 76g of red and processed meat a day – equivalent to a rasher of bacon and a slice of roast beef – are 20 per cent more likely to develop the cancer than those who eat 21g a day, researchers found.
Bowel cancer is the fourth most common cancer in the UK and the second biggest cancer killer, according to Bowel Cancer UK. More than 16,000 people die from the disease in the country every year.
Current government guidelines state consumers should “on average eat no more than 70g of red and processed meat a day”. A rasher of bacon or slice of ham weighs around 20g, and a lamb chop or thick slice of roast beef around 50g.
“Our results strongly suggest that people who eat red and processed meat four or more times a week have a higher risk of developing bowel cancer than those who eat red and processed meat less than twice a week,” said Professor Tim Key, co-author of the study at Oxford University’s cancer epidemiology unit.
His team’s findings, published in the International Journal of Epidemiology, suggest that bowel cancer risk rises by 20 per cent with every 25g of processed meat eaten over a 25g baseline. In other words, it rises by a fifth with every rasher of bacon consumed.
Bacon, ham, sausages, and other processed meats have previously been classed as cancer-causing carcinogens by the World Health Organisation, and red meat as “probably carcinogenic.”
“But most previous research looked at people in the 1990s or earlier, and diets have changed significantly since then, so our study gives a more up-to-date insight,” said Prof Key.
For the new study, Prof Key and his team analysed the diets of 475,581 men and women aged 40 to 69 in the late 2000s. Over an average of just under six years, 2,609 developed bowel cancer.
There were 274 cases of bowel cancer among the 68,359 participants who ate around 21g of red and processed meat a day.
Among the 192,600 eating an average of 76g per day, there were 1,209 cases of the disease.
“The results of this study also question the recent focus on nitrite as the main culprit for colorectal cancer: the authors found very small differences between red and processed meat in this study, even though only processed meat contains nitrite,” said Dr Gunter Kuhnle, associate professor in nutrition and health at the University of Reading, who was not involved in the research.
“A reduction or removal of nitrite from meat products would therefore have only little impact on cancer risk. An increased consumption of fibre, as shown by this study, would be of considerably more benefit,” she added.
Public Health England’s chief nutritionist, Dr Alison Tedstone, said by cutting consumption of red and processed meat, consumers would also reduce salt and saturated fat in the diet – decreasing the risk of cardiovascular disease.
Dr Julie Sharp, head of health information at Cancer Research UK said: “The government guidelines on red and processed meat are general health advice and this study is a reminder that the more you can cut down beyond this, the more you can lower your chances of developing bowel cancer.”