The Mediterranean diet could help reduce the risk of a type of post-menopausal breast cancer with one of the worst outcomes by 40% according to a major new study funded by World Cancer Research Fund.

This large study, published in the International Journal of Cancer, looked at over 62,000 women over 20 years, and assessed how closely they followed the Mediterranean diet and how this affected their risk of breast cancer. The study found that those who adhered more closely to the Mediterranean diet had a 40% reduced risk of breast cancer – in particular the estrogen-receptor negative subtype – which usually has a worse outcome than other types of breast cancer.

The Mediterranean Diet pattern is one that includes a high intake of plant-based proteins, such as nuts, lentils and beans, whole-grains, fish and monounsaturated fats – also known as ‘good fats’, such as olive oil. This diet also has a low intake of refined grains such as white bread or white rice, red meat and sweets. Although the traditional Mediterranean Diet involves moderate consumption of alcohol, in this study alcohol was excluded from the criteria, as this is a known risk factor for breast cancer.

Breast cancer is the most common cancer in women in the UK with over 53,000 new cases each year. [1]

Evidence from World Cancer Research Fund already shows there are ways to help reduce breast cancer risk, such as avoiding drinking alcohol. Almost 12,000 cases of breast cancer could be prevented in the UK each year if nobody drank alcohol. [2] For cancer prevention in general it is important to eat a wide variety of whole-grains, pulses, fruit and vegetables.

Dr Panagiota Mitrou, Director of Research Funding at World Cancer Research Fund, said:
“This important study showed that following a dietary pattern like the Mediterranean Diet, could help reduce breast cancer risk – particularly the subtype with a poorer prognosis. With breast cancer being so common in the UK, prevention is key if we want to see a decrease in the number of women developing the disease.

“We would welcome further research that helps us better understand the risk factors for the different breast cancer subtypes.”

Professor Piet van den Brandt, lead researcher on this study at Maastricht University said:
“Our research can help to shine a light on how dietary patterns can affect our cancer risk.

“We found a strong link between the Mediterranean Diet and reduced estrogen-receptor negative breast cancer risk among postmenopausal women, even in a non-Mediterranean population. This type of breast cancer usually has a worse prognosis than other types of breast cancer”.