Can a diet rich in polyphenols improve the health of breast cancer survivors?

A diet rich in polyphenols could help to prevent negative health consequences after breast cancer. This study will aim to find out whether a diet rich in polyphenols is related to better health among breast cancer survivors.

  • Topic: Breast cancer
  • Institution: Queen's University of Belfast
  • Country: United Kingdom
  • Status: Ongoing
Researcher: Tilman Kühn

“Polyphenols are naturally occurring plant compounds that are found in many fruits and vegetables, and plant-derived beverages such as tea and coffee. They have proven to be beneficial for the prevention of cardiovascular diseases, which are very common among breast cancer survivors.

Polyphenols may also affect tumour recurrence, although human studies are lacking. Therefore, we are delighted that we can investigate whether polyphenol intake and polyphenols in blood are related to important health outcomes among breast cancer survivors for the first time, with the fantastic support of World Cancer Research Fund.” – Dr Tilman Kühn

Grant title

Polyphenols and health outcomes among breast cancer survivors: A prospective biomarker study


Due to modern treatment, life expectancy for women with breast cancer is very good and is often similar to women without breast cancer. Despite better therapies, there is still an increased risk of a recurring cancer for some breast cancer survivors. Furthermore, many breast cancer therapies may have long-term side-effects, such as increased risks of having high blood pressure, a heart attack, or osteoporosis.

A diet rich in polyphenols, constituents naturally occurring in many plant-based foods and beverages, could help to prevent negative health consequences after breast cancer. However, a comprehensive study among breast cancer survivors investigating associations between polyphenol intake and health outcomes has not yet been carried out.

Aims and objectives

The aim of the present study is to find out whether a diet rich in polyphenols is related to better health among breast cancer survivors. We will analyse if women with a higher intake and higher blood levels of polyphenols have lower risks of recurring breast cancer and dying (from breast cancer or others causes). As it is known that breast cancer treatments may lead to cardiovascular diseases, diabetes and osteoporosis, we will also analyse if higher polyphenol levels protect women with breast cancer against these diseases.

How it will be done

To find out whether polyphenols may exert beneficial health effects, we will use a so-called prospective cohort study of 1,900 women who were diagnosed with breast cancer. Data was collected on individual breast cancer diagnoses and treatment, co-morbidities, but also on diet and lifestyle, and a blood sample was obtained.

The study will assess polyphenol intake among the participants and will measure 35 different polyphenols in stored blood samples. Using comprehensive statistical analyses, the study will find out whether polyphenol intake and blood concentrations are related to important health outcomes, namely breast cancer recurrence and dying, but also high blood pressure, diabetes, and osteoporosis. We will further investigate whether the potential health effects of polyphenols are more pronounced among women who received particular cancer treatments that are known to cause cardiovascular diseases, diabetes, and osteoporosis.

Potential impact

Our study will be the first comprehensive and large study among humans to assess whether polyphenols are actually beneficial to women with breast cancer. The study will show whether a diet rich in polyphenols is related to longer life expectancy and lower risk of cancer recurrence among women, who had breast cancer.

The study will further show whether polyphenols have the potential to mitigate long-term side-effects of breast cancer treatments on cardiovascular and bone health. Thus, our study is a highly relevant to breast cancer survivors, and we expect it to have an immediate impact on dietary recommendations for this large group of women.