What causes cancer? Part 3
Lifestyle factors
Diet and other lifestyle factors may increase or decrease the risk of developing cancer. For example:
- If you eat a lot of fruit and vegetables you have a reduced risk of developing certain cancers. The exact way in which they protect against cancer is not fully understood. These foods are rich in vitamins and minerals, and also contain chemicals called 'anti-oxidants'. They may protect against damaging chemicals that get into the body. We should all eat at least five portions of fruit and vegetables per day (some experts recommend even more).
- Eating too much fatty food possibly increases the risk of developing certain cancers.
- The risk of developing certain cancers is increased by: obesity, lack of regular exercise, and drinking a lot of alcohol.
Radiation
Radiation is a carcinogen. For example, exposure to radioactive materials and nuclear 'fallout' can increases the risk of leukaemia and other cancers. Too much sun exposure and sunburn (radiation from UVA and UVB) increase your risk of developing skin cancer.
The larger the dose of radiation, the greater the risk of developing cancer. But note: the risk from small doses such as from a single X-ray test is very small.
Infection
Some viruses are linked to certain cancers. For example, people with persistent infection with the hepatitis B virus or the hepatitis C virus have an increased risk of developing cancer of the liver. But, most viruses and viral infections are not linked to cancer.
Immune system
People with a poor immune system have an increased risk of developing certain cancers. For example, people with AIDS, or people on immunosuppressive therapy.
Your genetic make-up
Some cancers have a strong genetic link. For example, in certain childhood cancers the abnormal gene or genes which may trigger a cell to become abnormal and cancerous are inherited. Other types of cancer may have some genetic factor which is less clear-cut. It may be that in some people their genetic make-up means that they are less resistant to the effect of carcinogens or other factors such as diet.




