Diet is responsible for up to 80,000 cases of cancer each year in the UK, according to a leading researcher speaking today (Tuesday) at Cancer Research UK's conference in Harrogate.
Dr Tim Key, a principal scientist on the European diet study EPIC, says that around a third of these can be put down to alcohol and obesity alone. However, Dr Key says that the exact causes of the remaining two thirds are largely unknown.
Dr Key, who is based at Cancer Research UK's Epidemiology Unit in Oxford, explains: "Research suggests that diet is second only to smoking as a cause of cancer. But the effects of our eating habits are complicated and we are only beginning to understand which foods contribute to the disease.
"What we do know is that alcohol consumption and obesity are important causes of cancer and, while alcohol consumption is increasing in UK women, obesity is on the rise in both sexes."
Overall, alcohol consumption is responsible for six per cent of cancers in the UK, while obesity is believed to cause five percent of cases.
Alcohol is known to cause cancers of the mouth, throat, food pipe and liver and the risk with alcohol is much higher if you also smoke. Alcohol also causes a small increase in the risk for breast cancer. Obesity contributes to breast, womb, kidney and bowel cancer.
Dr Key adds: "Other factors, such as red meat, preserved meat and salty foods may also increase the risk of certain cancers but the relationship is not yet clear."
Cancer Research UK along with the Medical Research Council are funding the English arm of EPIC, a Europe wide study of the effects of diet on cancer rates.