People who stick to NHS guidelines on red and processed meat consumption still increase their risk of bowel cancer by a fifth compared with those who eat very small amounts, a study part-funded by Cancer Research UK found.
The Department of Health said while meat was a good source of protein, vitamins and minerals, people should cut their intake of red and processed meat to about 70g a day, which is the average daily consumption in the UK.
The World Cancer Research Fund (WCRF) said there was strong evidence that eating processed meat such as salami, bacon and ham was a cause of bowel cancer, while eating a lot of red meat such as beef, lamb or pork also increases the risk.
For the new study, published in the International Journal of Epidemiology, experts examined data from 475,581 people aged 40 to 69 at the start of the study and followed them for an average of 5.7 years.
During this time, 2,609 people developed bowel cancer.
The study found people consuming an average of 76g a day of red and processed meat had a 20 per cent higher risk of bowel cancer compared with those who ate 21g a day.
For red meat only, the risk was 15 per cent higher for people who ate 54g a day – about one thick slice of roast beef or one lamb chop – on average compared with those who had 8g a day.
For processed meat only, the risk was 19 per cent higher for those who had an average of 29g a day – about one rasher of bacon or a slice of ham – compared with those who had an average of 5g a day.
There was some good news however, with those people having a high intake of fibre from bread and breakfast cereals lowering their risk of bowel cancer by 14 per cent. Around one in every 15 men and one in every 18 women will develop bowel cancer during their lifetime.
Cancer Research UK’s expert in diet and cancer, Professor Tim Key, who co-authored the study, said: “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.
“There’s substantial evidence that red and processed meat are linked to bowel cancer, and the World Health Organisation classifies processed meat as carcinogenic and red meat as probably carcinogenic. 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 that is relevant to meat consumption today.”