As the causes of breast cancer aren't fully understood, at the moment it's not possible to know if it can be prevented.
If you're at increased risk of developing the condition, some treatments are available to reduce the risk.
Studies have looked at the link between breast cancer and diet. Although there are no definite conclusions, there are benefits for women who:
maintain a healthy weight
exercise regularly
have a low intake of saturated fat and alcohol
It's been suggested that regular exercise can reduce your risk of breast cancer by as much as a third. Regular exercise and a healthy lifestyle can also improve the outlook for people affected by breast cancer.
If you've been through the menopause, it's particularly important that you're not overweight or obese.
This is because being overweight or obese causes more oestrogen to be produced, which can increase the risk of breast cancer.
Being overweight may not be as unhealthy as it was 40 years ago," BBC News reports. New research has found a body mass index (BMI) of 27 is linked to the lowest rate of death – but someone with a BMI of 27 is currently classed as being overweight. BMI is a score calculated by dividing your weight (usually in kilograms) by the square of your height (usually in metres and centimetres). Currently, a BMI of 25 to 29.9 is classified as being overweight. Researchers looked at 120,528 people from Copenhagen, recruited from 1976 to 2013, and separately compared those recruited during the 1970s, 1990s and 2000s. They were followed up until they died, emigrated, or the study finished. The BMI linked to the lowest risk of having died from any cause was 23.7 in the 1970s group, 24.6 in the 1990s group, and had further risen to 27 in the 2003-13 group. It may be the case that the suggested upward shift in optimal BMI is the result of improvements in preventative treatments for weight-rela...