A new study has found that women who exercise energetically for an hour a day can cut their risk of breast cancer – regardless of their weight or age.
According to findings released at the European Breast Cancer Conference in Glasgow, Scotland, exercising vigorously for an hour a day can reduce chances of the disease by 11 per cent. Exercising for longer will increase protection further still compared with the least active women.
French researchers examined results from 37 studies involving more than four million women. They found women of any age or size who exercise for an hour a day all get a similar benefit, including those with the most aggressive cancers.
Because the results are independent of body mass index, BMI, the protective effects must be due to more than weight control, they said. The age at which sporting activity starts appears to be ‘immaterial’, researchers said.
The gain seems to be cancelled out in women taking hormone replacement therapy Professor Mathieu Boniol, research director at the International Prevention Research Institute in Lyon, France, said: “These are all the studies looking at the relationship between physical exercise and breast cancer risk that have been published to date, so we are confident that the results of our analysis are robust.”
He noted that exercise was a low cost, simple strategy to reduce the risk of a disease that currently has a very high cost, both to healthcare systems and to patients and their families. “It is good news both for individuals and for policy makers. Adding breast cancer, including its aggressive types, to the list of diseases that can be prevented by physical activity should encourage the development of cities that foster sport by becoming bike and walk-friendly, the creation of new sports facilities, and the promotion of exercise through education campaigns.”
The study focused on vigorous exercise, but previous research suggests even moderate activity in the form of walking an hour a day leads to a lower risk compared to women who were least active.