Cancer and its causes

The more you know about cancer, the better placed you are to cope with it

Cancer will affect most of us during our lives, either directly or indirectly. By improving our understanding of cancer, we become better placed to make lifestyle choices and take precautions which can reduce our cancer risk.

Everyone should be aware of symptoms for early detection and, for those diagnosed, understanding common treatment methods, side effects and common questions to ask your doctor can make a huge impact on how you navigate through your cancer experience. Knowledge and understanding can decrease fear and empower you to make the best possible choices for your health and well-being.

In a world where information is only a click away, it’s hard to know what to believe about cancer. False information can lead to unnecessary worry, or worse, lead you to ignore actual symptoms or make unhealthy choices in life. There are many myths about cancer and here we can help you to separate the fact from fiction.

1. No-one in my family has cancer, so I must be risk-free

While some cancers are hereditary, most cancers are caused by genetic changes that take place as a result of ageing and exposure to environmental factors, such as tobacco smoke. Other factors, such as your diet and level of physical activity, may also influence your risk of developing cancer. So even if no one in your family has cancer, it doesn’t mean that you are absolutely risk-free.

2. Eating ‘superfoods’ can prevent cancer

The word “superfood” is a marketing term used to describe foods that have special health benefits, and that are often claimed to prevent cancer. While some of these foods do have specific health benefits, it is unlikely that any single food alone can make a significant difference to your cancer risk. It is widely acknowledged, however, that a healthy and balanced diet can help to reduce the risk of cancer.

3. Deodorants can cause breast cancer

There is no scientific evidence to suggest that this is true.

4. UV rays will not harm my skin on a cloudy day

As much as 80% of the sun’s ultraviolet rays can penetrate through clouds. Just because you can’t see the sun, does not mean harmful UV rays can’t cause damage to your skin.

5. Sugar ‘feeds’ cancer cells

While you should limit sugary foods as part of a healthy diet and to avoid gaining weight (which can increase your risk of getting cancer), there are no studies that show eating sugar will make your cancer worse or, if you stop eating sugar, that your cancer will shrink or disappear.

6. Second-hand smoke doesn’t give you cancer

This is not true. Second-hand smoke (the smoke exhaled by someone smoking a cigarette, cigar, pipe of hookah) has more than 70 toxic chemicals known to cause cancer. It can cause lung cancer in people who do not smoke themselves and is especially dangerous for children, babies, and pregnant women.

Additionally, third-hand smoke is the residual nicotine and other harmful chemicals left by tobacco smoke which clings to hair, skin, clothes, furniture and other surfaces. Contact with surfaces containing third-hand smoke can lead to tobacco-related health risks for children and non-smoking adults.

7. Smoking will only increase the risk for lung cancer.

Whilst tobacco is a major cause of lung cancer and up to 90% diagnoses are linked to smoking, there are a number of other cancers that can be caused by smoking too. Tobacco use can increase the risk for nasopharyngeal (head and neck), mouth, lip and nose cancers and many other cancers found in major organs such as the stomach, kidney and bladder. Smoking is also a major contributing risk factor for heart and respiratory diseases. 

All forms of smoking, second-hand smoke and even third-hand smoke (the residual nicotine and other harmful chemicals left by tobacco smoke which clings to hair, skin, clothes, furniture and other surfaces) can have serious effects on your health. Every day you are exposed to tobacco increases your risk of cancer and other diseases, so please quit today!

If you have no symptoms, you don’t have cancer

In its early stages, cancer often has no symptoms and can go unnoticed. Signs of cancer are usually first detected by a doctor during a routine check-up. Be aware of your body and the common symptoms of cancer along with early detection tests and how often they should be performed for you. If you do notice any unusual health concerns or symptoms, consult your doctor.

8. Breast cancer only affects women, not men.

While breast cancer is most common in women, there are still a small percentage of men who are diagnosed with this type of cancer. Men with breast cancer often present with a more advanced disease stage primarily due to lack of awareness and delayed diagnosis. Like women, men should check themselves regularly for lumps or changes in the breast area and seek medical advice if anything unusual is found.

9. There are herbal products that can cure cancer?

Although complementary therapies have been shown to help patients cope with the side effects of cancer treatment, no herbal products have been clinically proven to effectively treat cancer. Some herbal remedies may even react harmfully when taken during your cancer treatment, and therefore you should always discuss any complementary medicines or therapy you might be considering with your doctor in advance.

10. Mobile phones cause cancer

Even though we still don’t know enough to rule out the possibility of risk entirely, there is currently no sound scientific evidence to link mobile phone use with an increased cancer risk. 

While it is true that some studies that have shown a potential link between the use of mobile phones and brain tumours, they include design flaws that affect the reliability of these results. According to Cancer Research UK, more reliable prospective cohort studies, which involve tracking a group of people’s behaviour and health over a period of time, have not found there to be a link between phone usage and brain tumours.

If you still have concerns, you can consider using the hand's free headset and microphone device to talk and switching your phone off as you sleep. However, we recommend you ignore this myth for now and, as with everything, to use your phone in moderation as part of a balanced and healthy lifestyle.

Cancer Myths information source:

  • Cancer Research UK
  • National Cancer Institute
  • Hong Kong Cancer Fund


Tel: (852) 3656 0800                                                                                

Donation Hotline
General donation:(852) 3667 6333
COF Monthly donation:(852) 3667 6332                                                      

  1. Questions or comments: please use our comments page
  2. Donation enquiries: [email protected]
  3. Media enquiries: [email protected] 
  4. Fundraising enquiries: see Get Involved