Can Exercise Reduce Your Risk of Breast Cancer?

You probably already know that exercise helps your heart, muscles and mood. If you’re looking for another reason to lace up your sneakers, here’s one: Staying active can lower your risk of breast cancer after menopause.

And if you do get breast cancer, moving your body after diagnosis may help you live longer and reduce the risk of it coming back.

Oncologist Halle Moore, MD, shares how exercise supports breast health and why every bit of movement helps.

How exercise lowers breast cancer risk

Research consistently shows the benefits of physical activity when it comes to breast cancer. A review of several studies found an average 25% risk reduction for those who stay fit.

A leading reason behind this is weight management. Overweight and obesity are risk factors for breast cancer in postmenopausal women. That’s because excess body fat makes it easier for cancer cells to grow.

“Fat tissue affects the hormonal environment in the body. This increases inflammation, which is associated with certain types of breast cancer,” Dr. Moore explains. “If you’re carrying more fat within your body, it can affect the growth of cancer cells.”

The risk is especially high after menopause. One study found that postmenopausal women in the highest body weight categories had an 82% increased risk for ER-positive breast cancer compared with those in the lowest body weight categories.

So, losing excess body fat after menopause may help lower your breast cancer risk.

But staying active has benefits outside of weight loss.

“Regular physical activity can also decrease inflammation and boost your immune system’s activity, which helps keep cancer cells at bay,” Dr. Moore adds.

How much exercise do you need?

Health experts generally recommend getting at least 150 minutes of moderate-intensity exercise per week. That’s 30 minutes of activity five days a week. (At moderate intensity, you should be able to carry on a conversation without gasping for breath.)

But when it comes to warding off breast cancer, more exercise may be better.

A 2015 study showed that exercising for 300 minutes a week ­— about five one-hour activity periods a week — led to larger decreases in body fat and a subsequent drop in breast cancer risk.

“That doesn’t mean you need to spend hours in the gym,” clarifies Dr. Moore. “Just being more active every day can bring really positive results.”

What types of activity count as exercise?

Not a fan of traditional workouts? That’s OK. Many forms of movement can help you meet your activity goals, like:

• Walking, hiking or running
• Swimming or water aerobics
• Cycling
• Dancing
• Doing physical chores, like gardening and yard work

If you’re new to fitness and feel overwhelmed by the idea of starting up a program, give yourself grace and time.

“Slowly incorporate exercise into your weekly routine, starting with a reasonable amount you can build on,” advises Dr. Moore. “Eventually, you should be able to add some type of physical activity into every day.”

And it’s always a good idea to talk to your healthcare provider before starting an exercise program.

Exercising after a breast cancer diagnosis

Even if you’ve stayed active for years, breast cancer can still happen. Maintaining movement can continue to play an important role in your recovery. An analysis of studies showed that physical activity after diagnosis was associated with:

• A reduction in breast cancer recurrence
• Fewer deaths from breast cancer
• Fewer deaths from all causes, as exercise can lower your risk for heart disease, diabetes and other cancers

“Staying active may help with cancer treatment side effects, too, like easing fatigue and depression and lowering your risk of lymphedema,” says Dr. Moore.

Final thoughts

Staying fit doesn’t eliminate your breast cancer risk. This disease has many other risk factors you can’t control, like genetics. But it can go a long way to make a positive impact.

“Whether your goal is to lower your risk or recover after treatment, moving your body regularly can make a meaningful difference,” encourages Dr. Moore.