Even though it is not known why cancer occurs, there is proof that certain things can increase your chance of developing the disease.

Research has shown that some of these risk factors affect the DNA of cells in the body organs, which can result in abnormal cell growth and may cause tumors to form.


A risk factor is anything that affects your chance of getting a disease such as cancer. Different cancers have different risk factors. For example, unprotected exposure to strong sunlight is a risk factor for skin cancer. Smoking is a risk factor for many cancers. But risk factors don’t tell us everything.

Having a risk factor, or even several risk factors, does not mean that you will get the disease. And many people who get the disease may not have had any known risk factors.

These cancer risk factors they fall into four broad categories, which may overlap. In some cancers, different risk factors may work together to increase your cancer risk.

The factors that fall into this category are the ones you have the most control over. By following these guidelines, you can significantly reduce your risk of developing cancer.

Don’t use tobacco products:

Smoking and using smokeless tobacco are directly linked to many kinds of cancer.

  • If you don’t smoke, never start.
  • If you do smoke, quit. The chances of getting lung cancer gradually decrease once you stop smoking.
  • Avoid breathing second-hand smoke, which increases your risk for heart and lung diseases, including cancer.

Avoid harmful ultraviolet (UV) rays:

UV radiation from the sun the main cause of skin cancer.

  • Avoid being in the sun when ultraviolet rays are strongest. During the summer, that is from about 11 a.m. to 3 p.m. A general rule is to avoid the sun when your shadow is shorter than you are.
  • Use a sunscreen with a sun protection factor (SPF) of 15 or higher. You want to use one that blocks UVA and UVB rays. Wear protective clothing to help block the sun’s rays

Maintain a healthy diet:

Research points to a link between a high-fat diet and certain cancers, such as cancer of the breast, colon, uterus and prostate. The good news is studies suggest that foods containing fibre and certain nutrients help protect against some cancers.

  • Eat a lot of fruits, vegetables, grains and beans. Include lean meat and low-fat dairy products in your diet.
  • Don’t eat a lot of fat.
  • Stay at a healthy weight.
  • Most days, include in your routine 30 minutes of moderate to vigorous activity.


Drinking large amounts of alcohol increases your risk of cancer of the mouth, throat, oesophagus (food pipe) and larynx (voice box). If you smoke and drink, you are at especially high risk of getting these cancers. Alcohol also can damage your liver and increase your risk of liver cancer.


Exposure to large doses of radiation can increase your cancer risk. X-rays used for diagnosis expose you to very little radiation, and the benefits nearly always outweigh the risks.

  • Talk with your doctor or dentist about the need for each X-ray.
  • Ask about the use of shields to protect other parts of your body.

You are more likely to get cancer when an altered or changed gene is passed on to you from one of your parents. This link between genes and cancer is often strongest in families where:

  • Cancer develops at a much younger age than average
  • Cancer develops in more than one generation
  • More than one type of cancer develops in the same close relative
  • Cancer develops in both breasts
  • Breast cancer develops in a man
  • Cancer develops in several close relatives
  • Several rare cancers develop in a family

There are chemicals or substances used in workplaces that may put you at increased risk for developing some cancers. For instance, asbestos and radon are linked with a higher cancer risk. Try to reduce your exposure to these substances and always wear protective equipment when it is available.

Certain health conditions may increase your risk for some cancers. Among these are colon polyps (abnormal tissue growths in the lining of the bowel) , previous cancer and Hepatitis B and C infections.