Women who frequently eat small amounts of red meat could be massively increasing their chances of developing breast cancer, researchers say.
Eating as little as 2oz of beef, pork or lamb every day can increase the risk of contracting the disease by 56 per cent in older, postmenopausal women, they warn.
And eating larger amounts of processed meats, such as sausages, bacon, ham and pies, pushed the risk to 64 per cent for the same group.
Women who frequently eat small amounts of red meat could be massively increasing their chances of developing breast cancer
Even younger women, who have yet to hit the menopause, are statistically more likely to develop the disease if they eat red meat daily, according to researchers at Sheffield University who believe that red meat is contributing to the onset of breast cancer because it is a rich source of saturated fat.
Lead researcher Janet Cade, a professor of nutritional epidemiology and public health at the university, said: 'The findings are robust. Women consuming the most total meat, red meat and the processed meat were at the highest risk compared with non-meat eaters, although red and processed meat were only statistically significant post-menopausally.'
The research, published today in the British Journal of Cancer, involved 35,000 women aged between 35 and 69 who were studied over eight years.
At the start of the trial, they were asked to complete a 217-item food questionnaire from which they were divided into three groups - high, medium or low meat eaters.
They were compared with women in the sample who ate no meat.
The researchers also took into account smoking, weight, fruit and vegetable intake, class education and use of hormone replacement therapy.
Professor Cade said she was surprised that such a small amount of meat appeared to have a large effect.
A 2oz portion equates to just half a lamb chop or two thin slices of roast beef.
'This is a complex piece of work and it was designed specifically to compare different patterns of diet,' she added.
'Really these results apply to all women. I am not suggesting that everyone should become a vegetarian, that would be unrealistic, but the findings were strong and I think we should pay attention to them.'
The research follows similar studies which highlight the link between breast cancer and red meat.
Last year, U.S. researchers found that younger women who regularly ate 4.5oz of red meat a day were doubling their risk of developing breast cancer compared with those who ate it infrequently.
The research found that women who ate more than one and a half servings of red meat a day had almost double the risk of oestrogen-positive breast cancer - the most prevalent form - compared with those who ate fewer than three servings a week.
Researchers claimed the higher risk was caused by cancer - causing compounds in cooked or processed meat.
Henry Scowcroft, science information office at Cancer Research UK, said: 'Our best dietary advice to women worried about their breast cancer risk is to maintain a healthy body weight by taking regular exercise and avoiding large regular portions of fatty foods like red and processed meat and excess alcohol.'