Not all cancers can be prevented, but there are proven ways you can reduce your risk. We will look at the benefits of exercise, including how it can help to reduce the risk of cancer.
Being active can also be helpful for many people with cancer during and after treatment. We have a separate page if you’d like to learn more about physical activity for people with cancer.

Why Is Being Active Good For Me?

Here are some of the reasons why it’s important to remain active:

  • Maintain a healthy weight
  • Reduce risk of Cancer
  • Improve mood & stress
  • Reduce the risk of heart disease
  • Reduce the risk of dementia & depression
  • Reduce risk of Osteoporosis
  • Reduce risk of falls in older adults
  • Chance to socialise
  • Train your brain to learn new skills

You don’t need to become a marathon runner overnight or join the gym to be more active – you don’t even have to leave your home. What counts as exercise may surprise you. From playing family games, to doing household chores, read our advice on how to be more active.


Even adding small amounts of activity into your daily routine can help you lose weight or keep a healthy weight. Keeping a healthy weight lowers your risk of 13 different cancer types. This includes 2 of the most common types of cancer (breast and bowel) and 3 of the hardest to treat cancers (pancreatic, oesophageal and gallbladder).

But we know that keeping a healthy weight isn’t always easy. If you’re thinking about losing weight, check out our 10 simple top tips for a healthy weight.


Being physically active lowers breast cancer risk by helping us to keep a healthy weight. And there’s also evidence that doing lots of exercise can prevent breast cancer directly, in ways not related to our weight.
Scientists are looking at how this might happen. Here are 2 possible ways being active could prevent breast cancer:

Reducing hormone levels

Both being active and the amount of fat you have can affect the levels of some types of hormones in the body. Hormones are chemical messages that move around the body to tell different parts what to do.
Oestrogen and insulin are hormones that could encourage breast cells to divide more often. If cells divide too much and grow out of control this can lead to cancer. As keeping a healthy weight and doing lots of activity can reduce the levels of oestrogen and insulin in the body, this could help to prevent breast cancer.

Boosting the immune system

Being very active can give your immune system a boost, which makes it work more effectively. This means the body gets better at spotting cells which could go on to become cancer. It can then remove these cells before they cause harm.


We know that moving more and sitting less prevents bowel cancer by helping us to keep a healthy weight. There’s also evidence that being very physically active can reduce your risk of bowel cancer directly.

These are some of the possible ways being active could help to prevent bowel cancer:

Moving food through the bowel faster

The bowel helps us use the food we eat and breaks down anything we don’t need. This passes out of our bodies as poo. Being active helps move food through our bodies faster. This means anything harmful in food waste spends less time in our bowel, which may help to prevent bowel cancer.

Reducing inflammation

Inflammation is a normal way our bodies respond to damage. But if there’s too much, it can cause our cells to multiply more often, increasing cancer risk. Keeping a healthy weight reduces the risk of 13 cancer types. One of the reasons for this is that having less body fat can reduce inflammation levels around the body. It’s also possible that being very active helps prevent bowel cancer directly by reducing levels of inflammation in the bowel.


Being active doesn’t reduce the risk of lung cancer. A few studies have shown a reduced risk in people who are more active, but some of these studies didn’t fully consider the effect of smoking. In the UK, more than 7 in 10 lung cancer cases are caused by smoking. If you smoke, stopping completely is the best thing you can do for your health.


Sitting or lying down for long periods of time throughout the day isn’t good for our health. Even people who do lots of exercise might spend too much time being inactive during the rest of the day.

It’s not yet clear if spending lots of time sitting or lying down can increase the risk of cancer. This is an area of research that is still developing. Most studies haven’t taken weight or physical activity fully into account. This means that the results could be misleading.

But if you do spend long periods of time sitting at home or at work, it’s a good idea to get up and move about more regularly. Try going for a glass of water, doing bits of housework, or walking on the spot when taking calls.