Decorative image

Protective factors

Some factors can help to reduce the risk of breast cancer.

Being physically active

Various studies have shown that physical activity can reduce the risk of breast cancer.

An analysis of 31 studies found that women who did the most activity had a 12% lower risk of developing breast cancer compared with the least active women.

The analysis also showed that the more active a woman is, the more she can reduce her risk of breast cancer. For example, for every 2 hours a week a woman spends doing moderate to vigorous activity, the risk of breast cancer falls by 5%.

Activity can include:

  • having a physically active job
  • recreational exercise, such as walking, cycling or playing sport
  • chores such as ironing, gardening and cleaning

The reduced risk is probably because exercise lowers levels of insulin, hormones and growth factors in the body.

Breastfeeding

Breastfeeding lowers the risk of developing breast cancer, particularly if you have your children when you are younger. The longer you breastfeed the more the risk is reduced.

It is not completely clear why this is. But the reduced risk might be because the ovaries don't produce eggs so often during breastfeeding. Or it might be because breastfeeding changes the cells in the breast so they might be more resistant to changes that lead to cancer.

Aspirin and anti inflammatory drugs

Research has shown that women who regularly take aspirin or other non steroidal anti inflammatory medicines have a slightly lower risk of developing breast cancer. 

Remember though that aspirin can irritate the lining of your stomach and cause bleeding. So you should talk to your own GP before starting to take it regularly.

You shouldn't take these medicines if you have any history of stomach ulcers.

Medicines for women at higher risk

Some women who have family members with breast cancer have a higher risk of developing it than other women. Some medicines can help to prevent breast cancer in women at high risk. Taking a drug called anastrozole for 5 years can reduce the risk of breast cancer.

Recent research showed that if 1,000 women at high risk of breast cancer took anastrozole for 5 years, it prevented 35 cases of breast cancer. In women taking a similar drug called tamoxifen 21 breast cancers would be prevented.

Speak to your doctor if you have family members with breast cancer and you think you might be at risk of developing it.

Diet

A healthy diet can help to prevent breast cancer.

Last reviewed: 
11 Oct 2017
  • Familial breast cancer: classification, care and managing breast cancer and related risks in people with a family history of breast cancer
    The National Institute for Health and Care Excellence, 2015

  • Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective
    World Cancer Research Fund/American Institute for Cancer Research, 2007

  • Cancers attributable to reproductive factors in the UK in 2010
    DM Parkin and others
    British Journal of Cancer, 2011

  • Use of nonsteroidal anti-inflammatory drugs and reduced breast cancer risk among overweight women
    Y Cui and others
    Breast Cancer Research and Treatment, 2014 Jul;146(2):439-46

  • The information on this page is based on literature searches and specialist checking. We used many references and there are too many to list here. If you need additional references for this information please contact patientinformation@cancer.org.uk with details of the particular risk or cause you are interested in.

Information and help

Dangoor sponsorship

About Cancer generously supported by Dangoor Education since 2010.