Can cancer be prevented?
Many people believe that getting cancer is purely down to genes, fate or bad luck. But through scientific research, we know that our risk actually depends on a combination of our genes, our environment and aspects of our lives, many of which we can control.
Cancer is caused by damage to our DNA, the chemical instructions that tell our cells what to do. Things in our environment, such as UV rays, or our lifestyle, such as the cancer-causing chemicals in tobacco, can damage our DNA. This damage builds up over time. If a cell develops too much damage to its DNA it can start to multiply out of control – this is how cancer starts.
Find out more about what cancer is and how it grows.
Family history and inherited genes
Some people inherit damaged DNA from their parents, which can give them a higher risk of certain cancers. For example the BRCA genes are linked with breast, ovarian, prostate and other cancers. But the proportion of cancers caused by inherited faulty genes is small.
Read more about inherited genes and cancer.
How many cancers could be prevented?
In the UK, more than 1 in 2 people will develop cancer at some point in their lives. Every year, more than 331,000 people are diagnosed with the disease. But experts estimate that more than 4 in 10 cancer cases could be prevented by lifestyle changes, such as:
- not smoking
- keeping a healthy bodyweight
- cutting back on alcohol
- eating a healthy, balanced diet
- keeping active
- avoiding certain infections (such as HPV)
- enjoying the sun safely
- occupation (avoiding cancer risks in the workplace)
Surveys of the population have shown that people aren’t necessarily aware that all of these things are linked to cancer. For example, the Cancer Research UK funded Perceptions of Risk Survey in 2008 found that only 3% of the people polled knew that being overweight or obese could increase their risk of cancer.
Need some inspiration?
Jeff, Mark, Maria and Emilie have all made changes towards a healthier lifestyle. Watch them explain what inspired them to make a change, how they did it and the way they feel about their lifestyles now
Making lifestyle changes can be difficult, but there are so many benefits. Try to find tricks that make it easier to get into healthy habits, such as being active with a friend, keeping track of what you eat or drink, or letting your friends and family know about what you're doing.
You can read our tips and advice for making healthier choices in different areas of your lifestyle in this section. And there are lots of other sources of information and support, such as the Change 4 Life website or your GP or pharmacist.
Is prevention a guarantee?
Preventing cancer doesn’t work in the same way as preventing infectious diseases with vaccines.
‘Healthy living’ is not a cast-iron guarantee against cancer. But it stacks the odds in your favour, by reducing the risk of developing the disease.
For example, we know that it’s possible for a heavy smoker to live a cancer-free life, while someone who never touches cigarettes could develop lung cancer. But lots of large long-term studies clearly show that people who have never smoked are far less likely to develop or die from cancer than smokers.
In the same way, careful drivers cannot guarantee that they will never get into an accident due to events beyond their control, but they are much less likely to do so than reckless ones.
You can read more about understanding risk on our Science Blog.
Can lifestyle changes really make a difference?
Yes, and not just for cancer. In 2008, a large UK study worked out how a combination of four healthy behaviours would affect your health. These were: not smoking; keeping active; moderating how much alcohol you drink; and eating five daily portions of fruit and vegetables.
People who ticked all four healthy boxes gained an average of 14 years of life compared to people who did not do any of them. By the end of the study, they were less likely to have died from any cause.
You can read more about four healthy behaviours on our Science Blog.