30 minutes of daily physical activity can reduce your risk of breast cancer by at least 20%.

How likely am I to get breast cancer?

Breast cancer is the most common cancer in the UK. Overall, one in eight women develops the disease in their lifetime, but not everyone’s risk is the same. Some people will have a higher or lower risk than others.

Our chances of developing breast cancer depend upon a combination of our genes and bodies, lifestyle and life choices and surrounding environment.

There are some things that increase your risk that you cannot change, such as getting older. However there are other factors you can change to reduce your risk if you wish, such as being regularly physically active.

How much can I reduce my risk by being physically active?

After reviewing the best scientific evidence and consulting with experts, Breast Cancer Now estimates that women can reduce their risk of developing breast cancer by at least 20% by being regularly physically active.

Or to put it another way, a comprehensive study identified during our review suggests that if every woman in the UK was regularly physically active, 1 in 6 cases of breast cancer could be avoided each year. To help explain the reduction in risk, let’s think about two groups of women (see diagram on the right).

Being physically active means that four rather than five women out of 40 will develop breast cancer. That’s equivalent to a 20% reduction in risk. Regular physical activity can also help prevent and manage many other conditions, including heart disease, stroke, type 2 diabetes, other types of cancer, obesity, mental health conditions and musculoskeletal conditions.

Diagram: The first group of 40 women are not physically active. Over the course of their lives about 5 of them will develop breast cancer (based on women living to age 90). The second group of 40 women are regularly physically active throughout their lives. About four of them will develop breast cancer. This means 1 fewer woman out of 40 develops breast cancer.

What type of physical activity counts?

Any physical activity that is moderate intensity or higher will reduce your risk, provided you are active for at least 30 minutes a day. Moderate physical activity should make you warmer and breathe harder and make your heart beat faster, but you should still be able to carry on a conversation. You can do more intense physical activity if you wish.

Physical activity doesn’t have to be a gym session or going for a run (although they are options). There are so many activities to choose from, most of which are free to do.

Here are some ideas:

10 individual activities

  • Brisk walk in the park
  • Join a running club
  • Go for a bike ride
  • Go for a swim
  • Do an exercise video
  • A quick gym session
  • Try a new exercise class
  • Try power yoga2
  • Try a park boot camp
  • Give Zumba a go

10 group or family activities

  • Have a dance contest with the kids
  • Play tennis or badminton with friends
  • Play a round of golf
  • Take family and friends tenpin bowling
  • Learn a new type of dance
  • Actively play with kids
  • Go on a group hike
  • Take the family ice-skating
  • Get the family out biking
  • Play football in the garden

10 day-to-day activities

  • Brisk walk to work or the shops
  • Push a baby buggy, pram or wheelchair
  • Mow the lawn
  • Do some gardening
  • Wash (and wax) the car
  • Get vacuuming
  • Paint and decorate a room
  • Clear away leaves or sweep the paths
  • Walk up the stairs
  • Take the dog for a walk

How much physical activity is needed?

To reduce your risk of breast cancer, you need to be physically active on a regular basis. That means exercising for a total of at least 30 minutes a day, or a total of 3.5 hours a week. To keep your risk of breast cancer down, you’ll need to keep active throughout your life. Breast Cancer Now suggests you incorporate physical activity into your day-to-day routine, so it’s a change for good.

Watch our video to find out the science behind the statistics

How does physical activity reduce breast cancer risk?

We don’t yet know for sure how physical activity reduces breast cancer risk. We do know that maintaining a healthy weight helps to reduce risk, so physical activity may reduce breast cancer risk by helping us to keep our weight healthy. Some studies have shown that physical activity may reduce levels of oestrogen in the body – a hormone which is known to encourage the growth of some breast cancers. Other studies have shown that physical activity might help our bodies respond well to insulin, which may also influence the growth of breast cancers.

What if I can’t be physically active?

If you have limitations on the physical activity that you can perform due to a health condition, we recommend that you speak with your doctor about what it would be safe for you to do. They may also be able to help you work towards being more active in the future. There are other steps you can take to reduce your risk too, see below for more information

For specialist advice on physical activity for those with a disability, see NHS Choices

I’ve had breast cancer. Can being physically active help me too?

If you have breast cancer or have had breast cancer in the past, regular physical activity may be of benefit to you. Research suggests that regular physical activity can improve your chances of survival following a breast cancer diagnosis.

There is also some evidence that physical activity may reduce the risk of the breast cancer coming back, but we don’t know for sure yet whether this is the case.

Keeping active may also help you to cope with your cancer treatment and improve your quality of life, general health and mental wellbeing, both during and after treatment.

There is not enough evidence from studies to tell us precisely how much physical activity is needed, so Breast Cancer Now suggests that women aim for 3.5 hours of physical activity a week, checking first with your treatment team what is appropriate for you.

What more can I do?

There are other steps you can take to reduce your risk, such as maintaining a healthy weight and reducing the amount of alcohol you regularly drink.

Track your daily activities

We’ve developed a web resource called BRISK where you can find out more about the types of physical activities you can take up, register and track your daily activity, as well as share your own ideas for getting active and hear from other women about theirs. 

Visit the BRISK website

Information Standard logo

Information last reviewed: November 2013

Next review due: November 2016

Breast Cancer Now's health information is covered by NHS England's Information Standard quality mark. Find out more.

Useful publications and downloads