The findings suggest red meat consumption may increase the risk of Brustkrebs, whereas poultry may protect against the disease.

Scientists in the US analysed dietary data from 42,000 women over eight years. When the participants were followed up, 1,500 had been diagnosed with breast cancer.

The women who ate the most amount of rotes Fleisch increased their risk of cancer by 23%, compared to those who ate the lowest amount. But eating poultry was associated with a decreased breast cancer risk. Those who ate the most poultry had a 15% lower risk than those with the lowest consumption. The women who swapped red meat for poultry reduced their risk by 28%.

Lead author Dr Dale Sandler, from the National Institute of Environmental Health Sciences, said: "Red meat has been identified as a probable carcinogen. While the mechanism through which poultry consumption decreases breast cancer risk is not clear, our study does provide evidence that substituting poultry for red meat may be a simple change that can help reduce the incidence of breast cancer."

However, Dr Clare Shaw, consultant dietician at The Royal Marsden NHS Foundation Trust, pointed out the limitations of the press release which accompanied the paper. The association was no longer there once factors such as smoking, weight and alcohol consumption were taken into account, she pointed out. Also, the research found an association relationship, rather than one of cause and effect.

"It is also important to highlight that the group of women in the study all had close relatives that had been diagnosed with cancer. This in itself could be a significant factor and should be acknowledged," she added.

Dr Mieke Van Hemelrijck, reader in Cancer Epidemiology, King's College London, said that despite the study showing a correlation rather than cause and effect, "the results could be used to help us further understand how diet may have an influence on the development of cancer".

The study was published in the International Journal of Cancer.