A diet rich in coffee, fruit and vegetables may protect against breast cancer, research suggests.

According to a new study presented at the European Congress on Obesity in Glasgow, diets full of phenolic acids can protect against post-menopausal breast cancer.

Phenolic acids are found in coffee, fruits, vegetables and whole grains.

Rich sources include raspberries, blueberries, apples, citrus fruits, plums, onions, coffee, red wine, cocoa and wholewheat, rice, corn and oats.

The study was led by a team from the University of Navarra and the University of Jaen in Spain.

In a 12-year trial involving 11,028 women, diets featuring heavy consumption of hydroxycinnamic acids (a naturally occurring type of phenolic acid) reduced the risk of breat cancer by 62%.

Chlorogenic acids, a type of hydroxycinnamic acid found in coffee, fruits, and vegetables were discovered to have the strongest effect.

Women consuming the most of this type of nutrient had a 65% reduced risk of breast cancer compared with those consuming the least.

The researchers concluded: "A higher intake of hydroxycinnamic acids, especially from chlorogenic acids - present in coffee, fruits and vegetables - was associated with decreased post-menopausal breast cancer risk."

Dr Kotryna Temcinaite, research communications manager at Breast Cancer Care and Breast Cancer Now, said: "We've long known that eating fruit and vegetables as part of a balanced diet can help lower your risk of breast cancer by helping you maintain a healthy weight.

"While this study helps suggest a potential mechanism behind this benefit, further research is needed to understand the effect that phenolic acids found in foods such as fruit, veg and coffee may have on breast cancer risk.

"Supporting more women to make healthy lifestyle changes will be key to preventing more breast cancers - but the small number of breast cancer cases in this study makes it difficult to draw strong conclusions about the potential role of phenolic acids in cancer prevention."

Dr Temcinaite said follow-up studies would be necessary to better understand any link between phenolic acids and cancer prevention.

Tam Fry, chairman of the National Obesity Forum, said: "This research pinning the reduction of breast cancer to the level of fruit and vegetable consumption should suggest to older women that they now make eating five-a-day a permanent choice."