The researchers found that women often changed their diet after being diagnosed with breast cancer. They also found that the level of phytoestrogens in the diet did not affect factors associated with how well you are likely to do after treatment for breast cancer (your prognosis).
The trial recruited over 3,000 women who had been diagnosed with breast cancer. They filled out questionnaires which asked them about their diet and lifestyle before and after they were diagnosed with cancer. This included questions about portion sizes, cooking habits, which foods they ate most often and any supplements they took.
In 2011, the research team looked at the information for 1,560 women. These women filled in another questionnaire about a year after they were diagnosed. The research team compared this to what the women ate before they were diagnosed and found they ate
- 173 fewer calories each day
- More whole grains, fruit, vegetables and lean protein
- Less sugar, fat, red meat and refined grains
The trial team continue to follow up the people taking part in this trial. But their initial conclusions were that women with breast cancer significantly changed their dietary habits after their diagnosis.
In 2013, the research team looked at phytoestrogen intake in 1,797 women to see whether this affected the factors associated with how well the women were likely to do after treatment (their prognosis). The trial team found no evidence that the level of phytoestrogens affected prognosis. However there were some links between phytoestrogens eaten before diagnosis and certain risk factors for breast cancer, such as body weight and having children.
The research team continue to look at if and when cancer comes back in the women in this trial. They are looking at whether diet, and phytoestrogens in particular, affect how long women with breast cancer live for. We will update this page when this information is available.
As well as looking at these factors, researchers are also interested in finding out more about genes and breast cancer cells. A number of research teams are analysing samples of blood and cancer cells from women taking part in this trial, and from women in other trials. They are trying to find out more about things such as:
- which genes increase or decrease the risk of developing breast cancer
- why people develop different types of breast cancer
- any proteins which they could use to help diagnose breast cancer
- any proteins which may help doctors find out if the cancer has spread or not
This sort of research takes time. But everything we find out helps us understand more about why breast cancer develops and how best to treat it.
We have based this summary on information from the team who ran the trial. The information they sent us has been reviewed by independent specialists (peer reviewed
) and published in a medical journal. The figures we quote above were provided by the trial team. We have not analysed the data ourselves.