Researchers have warned that a typical English breakfast of fried eggs, sausages, bacon, mushrooms and tomatoes can put you at an increased risk of developing cancer.
The traditional dish enjoyed by millions raises the risk of bowel cancer by 63 per cent if it is eaten every day.
The dramatic warning was issued by doctors at the World Cancer Research Fund after a new study.
They believe that eating processed meats like sausages and bacon significantly increases people's risk.
The huge amount of calories can also lead to obesity, which is linked to many different types of cancer.
The doctors said the typical English breakfast of fried eggs, sausages, bacon, mushrooms and tomatoes can contain 700 calories.
Adding in extras such as black pudding and fried bread pushes the calorie content even higher, while saturated fat is also known to contribute to the risk of heart disease.
The research fund said there is convincing scientific evidence that excess body fat is linked to six different forms of cancer, including bowel cancer and breast cancer.
xperts now believe that, after not smoking, maintaining a healthy weight is the most important thing people can do to prevent them developing the disease.
"For some people, having a fry-up might seem like a good way to start the day. But if you are doing this regularly then you are significantly increasing your risk of bowel cancer, which is one of the most common cancers," The Daily Express quoted Professor Martin Wiseman, medical and scientific adviser for the fund, as saying.
"Only a third of people are aware of the link between processed meat and cancer, which means two-thirds are not in a position to make an informed choice about how much of it they eat.
"This is not a question of all or nothing because the more processed meat you eat, the greater your risk. For example, if you eat 150g of it a day then you will be increasing your bowel cancer risk by about two-thirds.
"But if you only eat 50g a day - roughly the equivalent of a sausage - then you will be increasing your risk by about a fifth. As well as the processed meat increasing the risk of bowel cancer, fry-ups also tend to be high in calories.
"We recommend people limit consumption of high-calorie or energy-dense foods because eating them regularly makes you more likely to gain weight. This is important because there is convincing evidence that excess body fat increases risk of six different types of cancer," he added.