Researchers from Harvard University, whose study has just been published in the journal Archives of Internal Medicine, claim women who walk for at least an hour a day are 15% less likely to develop breast cancer than those who walk for less than an hour a week.
The study focused on post-menopausal women, but since many other studies suggest physical activity is vital for reducing the risk of breast cancer, it's never too early - or too late - to start.
It could, of course, be argued that any type of exercise would do, since being overweight is a known risk factor for the disease. However the researchers also looked at different types of exercise and found brisk walking was more protective against breast cancer than other activities such as swimming and jogging.
That's particularly good news since walking can easily become part of your daily routine. You just have to go at a fairly brisk pace, which is around three or four miles an hour. In other words, not a casual stroll but a pace at which you can still hold a conversation but feel slightly out of breath.
Not convinced? What would it take for you to walk instead of drive, bus or tube to work?