Being Well

3 Common Cancer Myths vs. Reality

Contrary to popular belief, a negative attitude doesn't affect cancer survival.

When you search “causes of cancer” on Google, the information you find can be overwhelming at best, and fake and misleading at worst. Misinformation can cast doubt on your treatment plan and keep you from enjoying and living your life.

Chances are you’ll hear one of these cancer myths if you or a loved one has been diagnosed with cancer. Most of the time, those myths prey on fear, focus on mouse studies — which often don’t translate to how human bodies will react — or rely on other limited, statistically insignificant research. Here’s the reality behind three common myths related to cancer.

Myth: Sugar Feeds Your Cancer

Reality: Glucose, the form of sugar used most in the body, feeds every cell in our body and is vital to how our body functions. Cancer cells do use more glucose than normal cells. Yet no studies to date show that eating sugar causes your cancer to get worse, or that eliminating sugar will keep your cancer from spreading, according to the National Cancer Institute (NCI). Artificial sweeteners don’t cause cancer in humans either.

Appetite changes during treatment may make it more difficult for you to eat enough calories. Often, carbohydrates may be the only thing you can tolerate eating. Go ahead and have that milkshake. Instead of worrying about sugar, focus on optimizing your diet to optimize healing.

What should you worry about? Sugar does contain excess – and often empty – calories. Eating more calories than you burn can increase your weight and put you at risk for obesity, which is a risk factor for developing several types of cancer. The NCI Fact Sheet on Obesity and Cancer explains that relationship in more detail.

Myth: Negative Attitudes Increase Your Risk of Cancer or Affect Survival

Reality: “Stay positive.” You might hear that you need a positive attitude to get through cancer treatment or even to beat cancer.

If you’re a curmudgeon at heart, don’t worry, your negative attitude didn’t cause your cancer. And it doesn’t increase your risk of dying from it. A 2010 study that followed 60,000 people over 30 years found no link between personality traits and cancer survival, according to the American Cancer Society (ACS).

If stress or depression is the cause of your negative attitude, however, learning coping skills may help to boost your mental and physical wellness. Stress and depression can interfere with treatment or keep you from making healthy choices, according to the <a href=”″ target=”_blank” rel=”nooNCI Fact Sheet on Psychological Stress and Cancer. Depression can also be a side effect of cancer diagnosis and treatment. It can affect medication and treatment adherence, and keep you from taking care of yourself.

Myth: You Can Only Get Cancer If It Runs in Your Family

Reality: A family history of cancer and certain inherited genetic markers can increase your risk of developing certain cancers. That’s true, but that’s not the complete picture. For most cancers, the majority of people diagnosed have no family history or genetic predisposition to the disease at all. Only 5% to 10% of cancer cases are inherited, according to the ACS.

Genetic changes over time and lifetime exposure to chemicals, such as tobacco smoke and radiation, may increase your risk of developing cancer. Overall, 38% of men and women will be diagnosed with cancer in their lifetime, reported the NCI.

Arm Yourself With Facts

You may come across other cancer myths during your treatment. Search through UVA’s Your Center blog to arm yourself with the facts on common cancer myths and what causes cancer.

When in doubt, ask your cancer care team. It’s their job to stay up to date on the latest scientific evidence to treat your cancer and help you heal.

If you have questions about cancer myths, visit the Learning Resource Center at UVA Cancer Center. An on-site health educator can help answer your questions.

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Rita Colorito