Age, lifestyle, diet and reducing your risk

The exact reason why a person has developed cancer is not usually known. But we do know some of the things that cause, or influence, our risk of developing cancer. We call these things risk factors.

You can reduce your risk of getting cancer by making positive lifestyle choices. Not smoking, eating a healthy diet and keeping physically active are some of the ways you can do this.

But there are some risk factors you can’t control. Age is a major risk factor for cancer. In general, people over 65 are more likely to develop cancer than younger people (those under 50).

Making changes to your lifestyle doesn’t guarantee that you won’t develop cancer. Cancer develops because of many different factors, many of which we cannot control.&

This makes checking your body and taking part in cancer screening programmes really important for everyone. Your GP can give you more information about national cancer screening programmes and advice about reducing your risk of cancer.

What is the risk of getting cancer?

More than 1 in 3 people in the UK will get cancer during their lives. Everyone has a certain risk of developing cancer. A combination of genes, lifestyle and environment can affect this risk.

Most of the time we don’t know exactly what causes a particular cancer. But we do know some of the risk factors for that cancer. Risk factors are things that can make you more likely to develop cancer. They include being older, smoking and being overweight.

Having a particular risk factor doesn’t mean you will definitely get cancer. Some risk factors only slightly increase the risk of developing cancer.

Usually, cancer is due to a combination of several risk factors. But some risk factors are more likely to cause cancer than others. Smoking is a good example of this. Smoking will greatly increase your risk of getting lung cancer. About 9 out of 10 people who develop lung cancer are smokers. But not everyone who smokes will develop lung cancer.

For most people, increasing age is the biggest risk factor for developing cancer. In general, people over 65 are more likely to develop cancer than younger people (those under 50).

Cancer is very common and most of us have relatives who have had cancer. People often worry that a history of cancer in their family greatly increases their risk of developing it. But fewer than 1 in 10 cancers are associated with a strong family history of cancer.

How diet can help reduce your risk of cancer

Macmillan Specialist Dietician Helen Kennedy explains how a healthy diet can reduce your risk of cancer and help if you're having treatment.

About our cancer information videos

How diet can help reduce your risk of cancer

Macmillan Specialist Dietician Helen Kennedy explains how a healthy diet can reduce your risk of cancer and help if you're having treatment.

About our cancer information videos


One of the biggest risk factors is increasing age.

Cancer can occur at any age but the risk of developing a cancer increases as we get older. More than three out of five people who get cancer (63%) are over the age of 65, and more than a third (36%) are over 75.


Other risk factors can play an important role in the development of cancer.

Around 4 in 10 cancers in the UK could be prevented by lifestyle changes. Making these changes doesn’t guarantee that you won’t get cancer, but they will make it less likely and will improve your general health.

Give up smoking

If you smoke, giving up is the single most important thing you can do for your health.

In the UK about 1 in 5 cancers, and more than 1 in 4 cancer deaths, are linked to smoking. It increases the risk of many cancers, including cancers of the mouth, throat, lung, bladder, kidney, pancreas, bowel, stomach and cervix.

Breathing in other people’s smoke (passive smoking) also increases your risk of developing cancer. If you are worried about passive smoking, talk to your doctor or practice nurse.

Help is available if you want to give up smoking. Ask your GP for advice, or contact your national stop smoking service below:

Smokefree (England)

Tel 0300 123 1044 (Mon–Fri, 9am–8pm, Sat–Sun, 11am–4pm)


Smokeline (Scotland)

Tel 0800 84 84 84 (Mon–Sun, 8am–10pm)

Can Stop Smoking

Stop Smoking Wales

Tel 0800 085 2219 (Mon–Fri, 9am–5pm)

Stop Smoking Wales

Want2stop (Northern Ireland)


Keep to a healthy weight

More than half of adults in the UK (61%) are overweight.

Being overweight increases the risk of several cancers, including cancers of the pancreas, bowel, womb and kidney. It can also increase the risk of breast cancer after the menopause.

Being overweight can also lead to other health problems such as heart disease, high blood pressure or diabetes.

If you’re overweight, getting to a healthy weight is one of the best ways to reduce your risk of cancer. Your GP or practice nurse can talk to you about the ideal weight for your height.

The best way to lose weight is by eating a healthy diet and being more physically active.

Eat a healthy diet

A healthy diet can reduce your risk of cancer, particularly bowel cancer. It can also lower your risk of other health problems, such as heart disease and diabetes.

You should eat foods that are high in fibre, such as wholegrain bread and pasta, beans and oatmeal. Try to eat five portions of fruit and vegetables every day.

Limiting how much salt, red meat and processed meat you eat is also important. Processed meats are meats that have had preservatives added to them, or that have been preserved by salting, curing or smoking. They include sausages, ham and burgers.

Keep physically active

Many studies have found that regular physical activity can reduce the risk of cancer.

You should try to do at least two and a half hours of activity each week. This can be split into 10 to 30 minute sessions throughout the week. You can increase these times as you get used to exercising.

You don’t have to go to the gym to be active. Regular walking, cycling or swimming can be enough. During any activity, you should feel you are breathing quicker but still able to talk. Your pulse should be slightly faster than normal.

If you’re not used to doing exercise, your GP can advise you on getting started.

Limit how much alcohol you drink

Drinking alcohol, especially more than the recommended limits, can increase your cancer risk. About 4 in 100 cancers in the UK are linked to alcohol.

Alcohol increases the risk of cancers of the mouth and throat. It is also linked to cancers of the bowel, liver and breast. In general, the more you drink, the higher your risk.

NHS guidelines suggest that both men and women should:

  • not regularly drink more than 14 units of alcohol in a week
  • spread the alcohol units they drink in a week over three or more days
  • try to have several alcohol-free days every week.

A unit of alcohol is half a pint of ordinary strength beer, lager or cider, one small glass (125ml) of wine or a single measure (25ml) of spirits.

There is more information about alcohol and drinking guidelines at Drinkaware.

Take care in the sun

Spending some time outside in the sun helps you stay healthy. Our bodies use the UVB rays in sunlight to make vitamin D. This is important for bone health and reduces the risk of many illnesses, including cancer. But it’s also important to protect your skin from burning, as this can increase your risk of skin cancers.

If you’re going to be out in the sun for longer than a few minutes, use a suncream with a sun protection factor (SPF) of at least 30. You should wear loose, cotton clothes that cover your body, as well as a hat.

Avoid using a sunbed or sunlamp. If you want to look tanned, use fake tanning lotions or sprays.

Know your body

If you know your body and what’s normal for you, it will help you to be aware of any changes. People sometimes think a change in their body isn’t worth bothering their doctor about. Or they may feel embarrassed talking about it.

But if you notice a change in how you feel or how your body works, it’s better to be safe and get it checked. You should go to see your doctor if you have:

  • a lump anywhere on your body
  • sore or ulcer that doesn’t heal within three weeks
  • a mole that changes shape, size or colour, crusts over or bleeds
  • a cough or hoarse voice that lasts for more than three weeks
  • shortness of breath
  • loss of appetite, ongoing indigestion or difficulty swallowing
  • a change in bowel habit that lasts for more than three weeks
  • blood in your urine, bowel motions, semen, spit or vomit, or abnormal bleeding from your vagina
  • a need to pass urine more often or urgently, or pain when passing urine
  • unexplained weight loss or tiredness
  • an unexplained ache or pain that lasts for more than three weeks.

Most of the time, these changes aren’t due to cancer. But finding a cancer early can make a big difference to how successful treatment is.

There is more information on when you should talk to your doctor about changes in your body on the NHS website.

If you’re worried about any ache or pain, see your GP. It may be nothing to worry about, but it’s always good to get it checked rather than worry.


Cancer screening

Screening tests aim to detect cancer early, when treatment is most effective.

In the UK, there are screening programmes for bowel cancer, breast cancer and cervical cancer. If you’re registered with a GP, you should automatically be invited to screening when you reach the age each screening programme starts.

Finding cancer early can make a big difference to the success of treatment.

There’s more information about the screening programmes on these websites:

Population screening programmes - NHS (England & Wales)

NHS Inform - Screening (Scotland)

HSC NI (Northern Ireland)

If you are still worried

When someone close to you has a serious illness, you may start to worry about your own health. If it’s a family member, you may worry about having the same condition. You might find it helpful to talk to someone about your concerns.

If you are still worried, you can ask your GP for details of a local counselling service. You can also call our cancer support specialists on 0808 808 00 00.

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