Reducing the risk
A number of things may help reduce your risk of developing breast cancer.
Studies have looked at the link between breast cancer and diet and, although there are no definite conclusions at the moment, there are benefits for women who maintain a healthy weight, take regular exercise and who have a low intake of saturated fat and alcohol.
It's been suggested that exercising regularly (a minimum of 150 minutes or 2 hours 30 minutes a week) can reduce your risk of developing breast cancer by up to a third.
Read more about the physical activity guidelines for adults.
If you've experienced the menopause (when your monthly periods stop), it's very important you're not overweight or obese. This is because these conditions cause more oestrogen to be produced, which can increase the risk of breast cancer.
Read more about preventing breast cancer.
Studies have shown that women who breastfeed are statistically less likely to develop breast cancer than those who do not.
The reasons for this are not fully understood, but it could be because women do not ovulate as regularly while they're breastfeeding and their oestrogen levels remain stable.
Medicines called tamoxifen and raloxifene are available on the NHS for women with an increased risk of developing breast cancer.
These medicines may not be suitable if you've had blood clots or womb cancer in the past, or if you have an increased risk of developing these problems in the future. If you've already had a mastectomy to remove both breasts you will not be offered these medicines because your risk of developing breast cancer is very small.
Either tamoxifen or raloxifene can be used in women who've had the menopause.
A course of treatment with tamoxifen or raloxifene will usually involve taking a tablet every day for 5 years.
Raloxifene can cause side effects including flu-like symptoms, hot flushes and leg cramps. Side effects of tamoxifen can include hot flushes and sweats, changes to your periods and nausea and vomiting.
Tamoxifen can increase your risk of developing blood clots, so you should stop taking it 6 weeks before any planned surgery.
Tamoxifen and raloxifene are not currently licensed for reducing the chances of getting breast cancer in women with an increased risk of developing it. However, they can still be used if you understand the benefits and risks and your doctor believes the treatment will be helpful.
The NHS Breast Screening Programme provides free breast screening every 3 years for all women in the UK who are 50 years of age or over. In some areas, women aged 47 to 49 and 71 to 73 are also invited for screening as part of a trial looking at whether the screening age range should be extended.
NHS breast screening is not usually available for women under 47 years of age. This is because younger women tend to have denser breast tissue, which makes mammograms less effective at identifying abnormalities.
Speak to your GP if you're below screening age and worried about changes in your breasts, or you have a family history of breast cancer.
Read more about breast cancer screening.