What increases my risk of breast cancer?

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About risk factors

  • Risk factors increase your chance of getting breast cancer.
  • There are risks we can change, such as how much alcohol we drink, and risks we can't change, such as our age. 
  • Having a risk factor doesn't mean you will get breast cancer.
  • Sometimes people with no risk factors get breast cancer.
  • If you’re worried, talk to your GP or talk to one of our cancer nurses. Call our Support Line on 1800 200 700 or visit a Daffodil Centre. 

Things we can change

  • Alcohol: Drinking alcohol increases your risk of breast cancer. Alcohol causes around 1 in 13 breast cancers diagnosed in Ireland each year. You can reduce your risk by not drinking alcohol. The less you drink the lower your risk.
  • Weight: Staying a healthy weight decreases your risk of breast cancer. If you are overweight, even modest, sustained weight loss can lower your breast cancer risk.
  • Physical activity: People who are physically active have a lower risk of breast cancer. Any amount of physical activity is good for your health.
  • Breastfeeding: Breastfeeding decreases your risk of breast cancer. The longer a woman breastfeeds over the course of her life, the more she reduces her breast cancer risk. 
  • Hormone replacement therapy (HRT): HRT is a hormonal drug that is used to help manage the symptoms of menopause. Some types of HRT may increase the risk of breast cancer, but the increased risk is small and the benefits may outweigh the risks. Talk to your GP about your options. 
  • Oral contraceptive pill: The oral contraceptive pill (OCP) can increase your risk of breast cancer. Each person's risk will be different. Talk to your GP about what's right for you. 
  • Eating habits: A balanced healthy diet can help you to maintain a healthy body weight, which decreases the risk of cancer.
  • Smoking: While it's not clear if smoking tobacco increases breast cancer risk, we do know that smoking increases the risk of at least 15 other types of cancer. Quitting tobacco products reduces cancer risk.

Things we can't change

  • Age: Your risk of breast cancer increases as you grow older. Breast cancer is most common in women over 50, but younger women can get breast cancer too. 
  • Family history and inherited genes: Your risk of breast cancer is higher if a close member of your family (such as a mother, sister or daughter) had it under the age of 40  or if more than one first- or second-degree (aunt, uncle, grandparent) relative was affected. If you have a strong family history of breast cancer, there may be a faulty gene in your family that increases the risk of breast cancer. For example, the BRCA1, BRCA2 or PALB2 gene. Inherited faulty genes cause about 5-10 in every 100 breast cancers.
  • Dense breast tissue: If your breasts have more non-fatty (dense) tissue, your risk of breast cancer is higher than for a woman with less dense breasts. You can't tell your breast density by feeling or looking at your breasts. There is a lot we don't yet understand about the link between breast density and breast cancer. Researchers are trying to answer these questions.
  • Age when periods started and stopped: Your risk is higher if you started your periods early (before the age of 12) or had a late menopause (after the age of 55).
  • Children: Having no children or having your first child later in life (after age 30) slightly increases your risk.
  • Previous breast disease: Being diagnosed with breast cancer or atypical ductal hyperplasia (ADH) increases your risk of developing breast cancer in the future.
  • Radiotherapy: Having had radiotherapy to your chest area in the past increases your risk.

Reducing your risk of breast cancer

The most important things you can do to reduce your risk of breast cancer are to:

  • Check your breasts every month to spot any abnormal changes.
  • Take part in the BreastCheck screening programme. It’s free every 2 years for women aged 50 to 69.
  • Talk to your GP about earlier screening if you have a family history of breast or ovarian cancer.
  • Limit alcohol: The more you cut down, the more you can reduce your risk. Limit your breast cancer risk by drinking no more than one standard drink a day.
  • Keep a healthy weight for your height.
  • Stay active: Women who are physically active have a lower risk of breast cancer than less active women. Try to do at least 150 minutes of moderate or 75 minutes of vigorous physical activity a week. Moderate activity makes you a little warm and out of breath, increases your heart rate and you can talk but not sing. Vigorous activity raises your heart rate and makes you sweat and feel out of breath.
  • Stop smoking.
  • Breastfeed your baby if you can: The longer a woman breastfeeds her baby, the more she reduces her breast cancer risk. It’s best to breastfeed your baby for at least the first six months, if possible.

Read more about reducing your risk of cancer.

For more information

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1800 200 700

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