Exercise lowers risk of breast cancer after menopause

Women who exercise regularly for four years after the menopause can “rapidly decrease” their risk of breast cancer, a new study has found.

The study found women who exercised just moderately saw their risk of cancer drop by up to 10 per cent, but those who had abandoned exercise regimes saw no benefit. Even low levels of exercise, would be enough to have an impact if carried out regularly.

It follows work published in March, which bought together 37 studies across 26 years to show regular physical exercise can reduce the risk of breast cancer in women of all ages by around 12 per cent.

Postmenopausal women have a higher risk of breast cancer, with the risk highest in those who experience it late. In the UK, 51 is the average age for a woman to reach the menopause, although some women will experience it in their 30s or 40s.

The study, published today in a journal of the American Association for Cancer Research, showed postmenopausal women who had regularly burned calories equivalent to four hours of walking per week saw a benefit.

Researchers analysed data from questionnaires completed by almost 60,000 women, enrolled into a French cancer study over eight years. Among these women, 2,155 were diagnosed with breast cancer.

The diagnosis rate was 10 per cent lower among those who had carried out regular exercise over the last four years. Those who had exercised regularly five to nine years previously but had since stopped did not see a lowered risk.

Sally Greenbrook, senior policy officer at Breakthrough Breast Cancer, says: “Being physically activity doesn’t need to be running or going to the gym - it can be anything from playing actively with your children, walking or gardening - anything that raises your pulse reduces your risk.

“Breast cancer is most common in postmenopausal women so it is great to see evidence like this which supports the message that physical activity in this age group is beneficial.”

The study is the first to demonstrate how quickly the link between exercise and decreased risk can develop after regular exercise starts and how fast it disappears once exercise stops.

The findings were independent of weight and the level of activity from earlier in the women’s lives.

Agnès Fournier, PhD, a researcher at the Institut Gustave Roussy in Villejuif, France, who helped carry out the research, said: “It was not [previously] clear how rapidly [the link between exercise and cancer risk] is observed after regular physical activity is begun or for how long it lasts after regular exercise stops. Our study answers these questions. We found that recreational physical activity, even of modest intensity, seemed to have a rapid impact on breast cancer risk.

“As a result, postmenopausal women who do not exercise should consider starting because their risk of breast cancer may decrease rapidly.”