If women change some aspects of their lifestyle now thousands of cases of breast cancer could be prevented over 20 years – a leading researcher predicts.
Reducing use of hormone replacement therapy (HRT), keeping a healthy bodyweight and exercising more are the key things women can do to cut breast cancer cases by more than 5,700 each year.
These figures will be presented tomorrow, on the first day of Breast Cancer Awareness Month, by Cancer Research UK epidemiologist Professor Max Parkin at the National Cancer Research Institute’s conference in Birmingham.
Each year more than 44,000 women in the UK are diagnosed with breast cancer and incidence rates have increased by more than 12 percent over the last decade. Prof Parkin predicts that without lifestyle changes the numbers being diagnosed annually will reach 58,000 by 2024.
Prolonged use of HRT has been identified as the leading lifestyle risk factor for breast cancer and Prof Parkin predicts that around 2,100 cases of breast cancer could be prevented each year if the number of women taking HRT continues to fall.
Scientific evidence shows that the risk of postmenopausal breast cancer in obese women is 25 per cent higher compared to women of normal weight. Prof Parkin calculates that a drop in obesity rates could prevent around another 1,800 cases each year.
Increased levels of physical activity among UK women could prevent around 1,400 cases each year. Currently only one in four women meets the government guidelines on exercise.*
Even small amounts of alcohol can increase the risk of breast cancer. Several studies have found that every alcohol unit drunk daily increases breast cancer risk by between 7-11 percent. If women kept their alcohol intake within government guidelines** a further 200 cases of breast cancer could be prevented each year.
Breastfeeding for six months also accounts for some risk reduction.
It is, however, important to recognise that overall an individual’s risk of cancer is a combination of genetic makeup as well as lifestyle and environmental factors.
Professor Parkin said: “Since breast cancer is predominantly a disease diagnosed in older women, as the population ages so the incidence of breast cancer is set to increase. If recent trends continue we can calculate that by 2024 there will be nearly 60,000 new cases compared with the latest figures of 44,000 new cases a year.
“But we also know that a number of lifestyle factors can influence a woman’s risk of breast cancer. If women begin to make changes in their lifestyle now then by 2024 one in 10 cases could be prevented.”
The predictions are based on the following:
that prolonged HRT use will continue to fall at the same rate as currently (by almost 50 per cent) over the next five years;
that levels of obesity over the next 10 years will return to 1980 levels when 8 per cent of women were obese compared with 23 per cent today;
*that exercise levels will increase so that, within three years, all women will exercise for at least 30 minutes five days a week;
**that, within three years, all women will drink within the government recommendations of no more than two alcoholic units a day;
that (as in Sweden) 72 percent of women in the UK breast feed for six months, currently achieved by 21 percent.
Sara Hiom, Cancer Research UK’s director of health information, said: “These calculations show us how lifestyle changes can reduce their risk of breast cancer. But every woman will make choices about their health based on their individual circumstances. For instance, there are good medical reasons why some women take HRT where the benefits outweigh the disadvantages.
“Leading a healthy life with a good diet, plenty of exercise and drinking a limited amount of alcohol does not guarantee that a person won’t get cancer but these healthy habits can help to cut the chances.”