Common Cancer myths and misconceptions

It’s easy to be overwhelmed with information when faced with a cancer diagnosis. Here we separate facts from fiction to help guide your decision making.

Misconceptions about cancer can lead to unnecessary anxiety and can hinder your ability to make good decisions. Let the latest science-based information be your guide.

If someone in my family has cancer, am I likely to get cancer, too?

Not necessarily. Cancer is caused by harmful changes (mutations) in genes. Only about 5 to 10 percent of cancers are caused by harmful mutations that are inherited from a person’s family, according to the US National Cancer Institute. In families with an inherited cancer-causing mutation, multiple family members will often develop the same type of cancer. These cancers are called familial or hereditary cancers. The other 90 to 95 percent of cancers are caused by mutations that occur during a person’s lifetime as a natural result of multiple factors such as aging and exposure to environmental factors including tobacco smoke and radiation.

If cancer is random, is there nothing I can do to prevent it?

At least 30-40% of cancers are preventable, says the Cancer Association of SA (CANSA). Potential cancer risks can be significantly reduced by avoiding cancer causing agents and by making healthy lifestyle choices, such as: not smoking, eating a healthy diet, limiting alcohol, exercising regularly, avoiding excessive sun exposure, as well as having regular screenings. Vaccination can also help prevent certain cancers: About 20% of cancers are caused by infections (mostly viral) for example, the human papilloma virus (HPV) is the major cause of cervical cancer, and liver cancer is caused by hepatitis B.

Does sugar ‘feed’ cancer?

Although research has shown that cancer cells consume more sugar (glucose) than normal cells, no studies have shown that eating sugar will cause cancer or make it worse. However, a high-sugar diet may contribute to excess weight gain, and obesity is associated with an increased risk of developing several types of cancer.

Do artificial sweeteners cause cancer?

Researchers have conducted studies on the safety of the artificial sweeteners, such as saccharin; cyclamate; aspartame; acesulfame potassium; sucralose; and neotame and found no evidence that they cause cancer in humans. All of these artificial sweeteners except for cyclamate have been approved by the US Food and Drug Administration.

Is cancer contagious?

Cancer is not a contagious disease. The only situation in which cancer can spread from one person to another is in organ or tissue transplantation. A person who receives an organ or tissue from a donor who had cancer in the past has a very low risk of developing a transplant-related cancer in the future.
In some people, cancers may be caused by certain viruses (HPV, for example) and bacteria (such as Helicobacter pylori). While viruses spread from person to person, cancers do not.

Can cancer surgery or a tumour biopsy cause cancer to spread in the body?

The chance that surgery will cause cancer to spread to other parts of the body (metastasize) is extremely low. Surgeons take many steps to prevent cancer cells from spreading during biopsies or surgery to remove tumours.

Do cell phones cause cancer?

Not according to the best studies completed so far. Cancer is caused by genetic mutations, and cell phones emit a type of low-frequency energy that does not damage genes.
Until more studies are completed, the Cancer Association of South Africa suggests exercising caution.

Do power lines cause cancer?

There is no evidence that power lines cause cancer. Power lines emit both electric and magnetic energy: The electric energy is easily shielded or weakened by walls and other objects and the magnetic energy is a low-frequency form of radiation that does not damage genes.

Can herbal remedies cure cancer?

Although some studies suggest that alternative or complementary therapies, including some herbs, may help patients cope with the side effects of cancer treatment, no herbal products have been shown to be effective for treating cancer.
In fact, some herbal products may be harmful when taken during chemotherapy or radiation therapy because they may interfere with how these treatments work. Speak to your doctor about any complementary and alternative medicine products—including vitamins and herbal supplements you use.

Are there risks associated with haemorrhoids?

There is no evidence to support the idea that haemorrhoids will become cancerous, but sometimes co-exist with cancer. Do not assume that all bleeding is caused by haemorrhoids so you should mention any rectal bleeding to a doctor.

One of the symptoms of colon or rectal cancer is bright red blood in the stools.

Are Stomach ulcers indicative of cancer?

Stomach ulcers are not necessarily a sign of cancer, although for a long time it was believed that stomach ulcers could result in stomach cancer. The danger of stomach ulcers is not so much the possibility that they may result in cancer, but rather that stomach cancer may be incorrectly diagnosed and treated as an ulcer.

Do deodorants cause breast cancer?

The best studies so far have found no evidence linking the chemicals typically found in antiperspirants and deodorants with changes in breast tissue.

Does colouring my hair increase the risk of cancer?

There is no convincing scientific evidence that personal hair dye use increases the risk of cancer.

When reading and researching cancer information, your best sources are a trusted doctor and evidence-based science. With the correct information you are equipped to ask questions and make informed choices about your care and treatment. Partnering with your doctor will give you a sense of control and empower you as you face this challenge.