Researchers have found that women who had a brisk walk several times a week reduced their breast cancer risk by 18 per cent.

Walking for up to two-and-a-half hours a week was the best protection, and even outstripped vigorous exercise.

The researchers, from the Fred Hutchinson Cancer Research Center in Seattle, also assessed the protective qualities of strenuous exercise among women when 18, 35 and 50 years of age. Women who were regularly exercising at age 35 had a 14 per cent reduced risk of breast cancer, a rate that was similarly achieved by women in the other two age groups.

But women aged between 50 and 79 who had a brisk walk for as little as one-and-a-quarter hours a week enjoyed the best protective effect. The risk decreased slightly more among women who walked for 10 hours a week, and among those with a body mass index (BMI) of less than 24, but it was almost as effective among women in the middle BMI tier of 24.1 to 28.4.

(Source: Journal of the American Medical Association, 2003; 290: 1331-6).