A major review of published research has found that certain key factors could impact the risk of death for women after a breast cancer diagnosis.
As part of World Cancer Research Fund International’s Global Cancer Update Programme, housed at Imperial College London, the review sought to understand the links between body weight, physical activity, diet and the risk of death after a breast cancer diagnosis.
Key findings of the review after a breast cancer diagnosis
Body weight
Strong evidence is that higher body weight, after diagnosis, increases the risk of death. 226 studies were analysed from around the world, comprising more than 456,000 women with breast cancer; among them, 36,000 died, and 21,000 of breast cancer.
Physical activity
Some evidence is that being more physically active could reduce the risk of death after a breast cancer diagnosis. Some evidence is that physical activity could reduce the risk of breast cancer recurrence.
23 studies were analysed from around the world, comprising more than 39,000 women with breast cancer; among them, around 5,000 died, and 2,000 of breast cancer.
Most studies looked at recreational physical activity, such as aerobics, walking and running, with limited studies on other types of activity.
Diet
Some evidence is that eating more dietary fibre could reduce the risk of death. Some evidence is that eating soy could reduce the risk of death and breast cancer recurrence.
Some evidence that people with certain healthy eating patterns have a reduced risk of death.
108 studies were analysed from around the world, comprising more than 151,000 women with breast cancer; among them, 14,900 died, and 5,900 breast cancer.
Breast cancer is the most common cancer among women in the UK, with 56,987 new cases in 2019. Three in 10 new cancer cases in women in 2019 were breast cancer.
In 2020, breast cancer was globally the most common cancer among women. There were an estimated 2.3 million cases and 700,000 deaths. As of 2020, 7.8 million women worldwide lived at least five years after a breast cancer diagnosis.
Dr Helen Croker, head of Research Interpretation at WCRF International, said: ‘For over 20 years, our recommendations have supported the creation of an environment where individuals can pursue, and governments can support, healthier choices to reduce cancer risk.’
‘We now hope to develop a set of recommendations specifically for people living with and beyond cancer so that, alongside their healthcare team, they have the latest evidence-based information about healthy eating, physical activity and weight. Analysing and interpreting the existing literature is the first step towards these efforts.’
Nikki Bednall, diagnosed with stage 3 breast cancer in 2017, said: ‘After my diagnosis and treatment, I made a few lifestyle changes to reduce my risk of health problems. These included maintaining a healthy weight, eating various healthy foods and exercising regularly.’
‘I know from experience the feeling of jumping through hoops after a cancer diagnosis. However, as the evidence from these reviews gets stronger, it gives me greater confidence that there are things I can do to help improve my chances of living beyond my breast cancer.’
Dr Doris Chan, a co-author at Imperial College London, said: ‘Many women living with breast cancer seek lifestyle advice. It is important that they have access to reliable information about healthy living.’
‘The findings from these reviews strengthen the case for women with breast cancer to be supported by their healthcare team to make positive behaviour changes. These could include eating a healthier diet and being physically active, all of which play a role in maintaining a healthy weight.’
