Women with breast cancer can double their survival chances if they eat more fruit and vegetables and get half an hour of exercise daily. Cancer researchers at Moores University of California discovered this when they tracked 1500 women with breast cancer over a period of nine years. The women had had breast cancer diagnosed by doctors 2 years before the study started.
American and British health authorities promote the Five A Day: make sure you get five portions of vegetables, fruit, vegetable juice or fruit juice every day. Potatoes don’t count, nor does fruit juice that contains no active ingredients. Orange juice and tomato juice do count.In the US 1 in 8 women gets breast cancer. Treatment consists of removing tumours, chemotherapy, radiation of affected tissue, and – if the cancer cells are of a type that reacts to it – years of anti-oestrogen drugs. Most of the women who took part in the study were undergoing hormone treatment and were on tamoxifen.
The researchers looked at whether the women were getting the Five a Day and whether they were physically active. The demands were not high. If the women went for a brisk half-hour walk 6 times a week they counted as physically active in the researchers’ eyes. The figure below shows that these women’s chances of survival were twice that of the other women.
After 9 years, of the women who got Five a Day and were physically active, 8 percent had died. Of the women who fulfilled neither of the criteria, 16 percent had died.
Overweight is a risk factor in breast cancer. But overweight women with a BMI of over 30 who ate healthily and were physically active had the same chance of survival as women whose weight was less.
The positive effect of a healthy diet and physical exercise was less in women who had tumours that did not react to estradiol and progesterone. For women who had a tumour that did not react to estradiol but did react to progesterone, a healthy lifestyle quadrupled their survival chances.
According to review articles, physical activity works in two ways to improve survival chances: physical activity reduces the concentration of oestrogens in the body, and, in addition, exercise increases sensitivity to insulin. [Breast Cancer Res. 2009; 11(5): 106.]
In healthy women, who have not got breast cancer, a healthy lifestyle still has a positive effect on the likelihood of them developing cancer. According to a 2008 review, an increase in physical exertion reduces the chance of developing breast cancer by 25-30 percent. The more exercise you get and the more intensive the kind of exercise, the lower the chance of breast cancer. [Br J Sports Med. 2008 Aug; 42(8): 636-47.]