Facts About Lifestyle and Breast Cancer
There is growing evidence of the link between healthy lifestyle choices and a lower risk of developing breast cancer. Being active, eating a well-balanced diet and maintaining a normal body weight are three simple but crucial lifestyle choices.
Physical Activity and Weight
Regular physical activity at all ages reduces the risk of breast cancer. Being physically active for more than 30 minutes a day could reduce breast cancer risk by 20%.
Not being active enough may increase the risk of breast cancer. This risk increases with increased sedentary time, particularly with watching television.
Maintaining a healthy weight throughout life could reduce the risk of postmenopausal breast cancer by 50%. Postmenopausal women who are overweight or obese and achieve a healthy weight may decrease their risk of breast cancer by 50%.
There is a link between alcohol consumption and risk of breast cancer. This risk increases with increasing alcohol intake, although any amount of alcohol has an associated risk. This is true for all types of alcoholic beverages. In the WHO European region in 2018, 25% of new cases of breast cancer were attributed to drinking a maximum of 2 drinks (20 g pure alcohol) per day.
Having children at a younger age (under 30) and having several children reduces breast cancer risk. Breast-feeding for long periods of time (eg, 2 years per child) and for multiple children is protective against breast cancer.
Menstrual factors such as early age of first menstruation (ie, 12 years or younger) and increasing age at menopause (ie, 53 years or older) increase the probability of developing breast cancer.
Menopausal Therapy and Use of Contraceptives
Recent use of menopausal hormone therapy (MHT) (particularly oestrogen plus progestin) and recent use of oral contraceptives are both associated with increases in overall breast cancer risk.
All types of MHT, except vaginal oestrogens, have been were associated with an increased risk of breast cancer, which increased with duration of use. Risks were larger for combined oestrogen-progestogen therapy than for oestrogen-only therapy. Women without a history of breast cancer are advised to discuss the risks and benefits of taking MHT with their doctor. For women with a history of breast cancer, MHT is generally not recommended.
Oral contraceptive use is associated with increased risk of breast cancer. Using them for 5 years was associated with a risk of dying from breast cancer. The risk declined 10 years after stopping using these therapies. Even contemporary hormonal contraceptives have an associated risk: A study in Denmark found a 19% increased risk of breast cancer among current and recent users of combined contraceptives.
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