Body weight   Tobacco smoke   Physical activity   Diet    Alcohol use    Environmental factors

Some of the research on breast cancer has focused on modifiable risk factors related to healthy lifestyle choices.

There is evidence that body weight, physical activity, alcohol use and exposure to tobacco smoke for young women before a first full-term pregnancy are linked to breast cancer risk. However, in the case of diet, environmental factors, and exposure to tobacco smoke later in life or after a first full-term pregnancy, the connections are not as clear, and more research is necessary to fully understand the links.

It is important to note that the factors above are also linked to diseases and conditions other than breast cancer. Therefore, adopting some of the healthy behaviours described in each of the detailed sections may help to improve overall health as well as reduce breast cancer risk.