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An Aboriginal woman in her 40s and a wise older woman in her 60s, smiling together, empowered to have a free breast screen.

Risk factors for breast cancer

A risk factor is anything that can increase your chance of developing a certain condition, such as breast cancer.

Some risk factors can be changed and some can't.

Getting older and being born female are the two biggest risk factors for breast cancer.

50+ stat

Most women diagnosed with breast cancer are over 50 years old.1518 

Risk factors you can’t change (non-modifiable) include:

  • getting older.
  • a family history of breast or ovarian cancer (ovarian cancer risk is often linked to breast cancer risk).
  • inherited genetic factors, such as a faulty or mutated gene.
  • medical history, such as previously having radiation therapy, breast cancer or another type of cancer.  
  • reproductive history, such as starting menstruation very young, reaching menopause late, or not having had children.
  • having dense breasts.

 

Around a quarter of all breast cancers could potentially be prevented through lifestyle and other changes.5536 

 lifestyle factors

Risk factors you can change (modifiable) include:

How to reduce your risk

Although some risk factors cannot be changed, there are things you can do to reduce your risk of breast cancer. 

Being overweight or obese

weight

Maintain a healthy body weight - keeping to a healthy weight range reduces risk of breast cancer. Breast cancer is more common in women who are above a healthy weight.

Drinking alcohol

no alcohol

Limit alcohol intake - the more you drink, the greater your breast cancer risk. If you do drink alcohol, limit your alcohol intake to 1 standard drink a day.

Not exercising enough

exercise

Engage in physical activity - active women of all ages are at reduced risk of breast cancer compared to women who do not exercise. Aim for at least 30 minutes of moderate-intensity physical activity every day. The more exercise you do, the bigger the benefits.

Taking some medicines, such as hormone therapy or an oral contraceptive pill

HRT

Menopausal hormone therapy (MHT)/hormone replacement therapy (HRT) - using hormone therapy that contains both oestrogen and progestogen is associated with an increased risk of breast cancer, with the risk increasing the longer you take it. If you are using hormone therapy, review your needs regularly with your doctor. 

Oral contraceptive pill - taking a ‘combined’ oral contraceptive (that contains both oestrogen and progestogen) is associated with a small increased risk of breast cancer. The risk reduces over time once you have stopped taking it. If you are using a combined oral contraceptive pill, review your needs regularly with your doctor.

 

More ways to reduce your breast cancer risk

Stop smoking

No smoking

Many studies show that tobacco smoking may be associated with an increased risk of breast cancer. We know quitting is not always easy, but it is one of the most effective things you can do to reduce your overall cancer risk and live a longer, healthier life. Visit iCanQuit or call Quitline on 13 7848 (13 QUIT)

Breastfeed

breastfeed

Breastfeeding can reduce the risk of breast cancer – and the longer the duration of breastfeeding, the greater the benefits.

Consume dairy

dairy milk

Eating and drinking dairy products may be associated with a decreased risk of breast cancer. Dairy products are foods made from the milk of mammals such as cows, sheep and goats.

Eat vegetables

No vegetables

Eating lots of veggies each day may be associated with a decreased risk of breast cancer. Vegetables can be either starchy (eg potatoes) or non-starchy (eg green leafy vegetables, carrots and onions).

Find out more information about breast cancer risks on the Cancer Australia website.  

Family history and inherited genetic factors 

It's important to note that most breast cancers are not caused by known genetic factors. Most women who develop breast cancer DO NOT have a family history of the disease.

Around 5% of breast cancers are due to a strong family history or genetic mutation, such as BRCA1 or BRCA2.1522

If you: 

  • have a first-degree relative (such as a parent, sibling, or child) diagnosed with breast cancer before age 50
  • are assessed by BreastScreen NSW as needing more frequent monitoring
  • are assessed by your doctor as being high risk,

it may be recommended that you have an annual breast screen from age 40.

If you have a blood relative diagnosed with breast cancer over 50 years old and no other contributing factors, then you are at similar risk to developing breast cancer as the general population. You will be offered a breast screen every two years.  

Speak to your doctor if you have questions about your family history of breast cancer. You should inform your doctor and BreastScreen NSW about any new cases of breast cancer diagnosed in your family since your last breast screen.  

Understanding your breast cancer risk

Having one or more risk factors does not mean you will develop cancer. To determine a woman’s risk of breast cancer it is important to consider all factors including age, genetics, behavioural and environmental factors.

Understanding your individual risk can provide peace of mind. You can complete a risk assessment yourself at no cost. The risk report can provide the basis for discussions between women and their doctors about their individual breast cancer risk, prevention and screening management.

Other useful links 

Get Healthy NSW offers free health coaching over the phone to help you reach your health goals, including cutting down on alcohol. Go to Drink less alcohol for information about alcohol and cancer risk. 

Eat healthy provides information and support to make healthy changes for cancer prevention. Also Healthy Eating Active Livingis a NSW Government website with healthy eating tips and information on free programs to get you active.  

Helping Mob Live Healthy and Prevent Cancer is a toolkit for the Aboriginal health workforce. 

Healthy Eating Active Living for the mob provides information and specific programs for Aboriginal people that can assist you and your family with what to eat and how to get active.

The Australian Dietary Guidelines tell you what foods to eat and how much. They also tell you what foods to avoid. 

Be more active provides information and support to reduce your risk of cancer. Also Australia’s Physical activity and exercise guidelines tell you how much exercise you should do each day. They also give tips on how you can get started. 

iCanQuit provides handy tools and practical advice to help you begin your quit smoking journey – and stay quit for good.  

If you have any questions about your personal risk of breast cancer, please speak with your doctor.  

Understand this important cancer screening test.

Find out if you are eligible to screen with BreastScreen NSW. 

What to expect before during and after your breast screen.

Find out about dense breast tissue and its impact on breast screening.