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Our 24/7 cancer helpline provides information and answers for people dealing with cancer. We can connect you with trained cancer information specialists who will answer questions about a cancer diagnosis and provide guidance and a compassionate ear.
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Our highly trained specialists are available 24/7 via phone and on weekdays can assist through online chat. We connect patients, caregivers, and family members with essential services and resources at every step of their cancer journey. Ask us how you can get involved and support the fight against cancer. Some of the topics we can assist with include:
For medical questions, we encourage you to review our information with your doctor.
There are a lot of rumors and myths about cancer that make it hard for people to know what’s true. Here are answers to some of the questions people ask about the causes of cancer.
A risk factor is something that raises the chance of getting a disease. Each cancer has its own risk factors. Having risk factors does not mean that someone will get cancer. Even when a person with a risk factor is found to have cancer, there’s no way to prove that the risk factor caused the cancer.
Some risk factors, like a person’s age or gene damage, can’t be changed. But some risk factors can be controlled. Tobacco use, contact with secondhand smoke, being in the sun, excess body weight, not being active, drinking alcohol, and not eating a healthy diet are risk factors that can be managed. Other risk factors include getting certain viruses and contact with certain kinds of radiation or chemicals.
Falls, bruises, broken bones, or other such injuries do not cause cancer. Sometimes a person might visit a health care provider for an injury and cancer is found. But the injury did not cause the cancer; the cancer was already there.
Your personality and emotions cannot cause cancer and will not affect the outcome of your cancer. Research shows that there is no connection between personality types or attitude and cancer occurrence or outcomes.
Researchers have done many studies to see if there’s a link between personality, attitude, stress, and cancer. It’s known that stress affects the immune system, but so do many other things. At this time, there is no clear evidence that a person's stress level affects their risk of getting cancer.
Sugar intake has not been shown to increase the risk of getting cancer, having cancer spread, or having it get worse. Still, sugars and sugar-sweetened drinks add a lot of calories to the diet and can cause weight gain, which is linked to cancer.
You can’t catch cancer from someone who has it. You won’t get cancer by being around or touching someone with cancer. When family and friends stay away, people with cancer may feel isolated and alone. They need your visits and support. To learn more, see Is Cancer Contagious?
Sometimes, certain types of cancer seem to run in some families. In some cases, this might be because family members share certain behaviors or exposures that increase cancer risk, such as such as smoking. Cancer risk might also be affected by other factors, like obesity, that tend to run in some families.
But in some cases the cancer is caused by an abnormal gene that is being passed along from generation to generation. Although this is often referred to as inherited cancer, what is inherited is the abnormal gene that can lead to cancer, not the cancer itself. To learn more, see Genetics and Cancer.
If you want to know more about how cancer starts and spreads, see What Is Cancer? If you have questions that aren’t answered here, please call one of our Cancer Information Specialists at 1-800-227-2345.
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as editors and translators with extensive experience in medical writing.
Chirac, V, Baban, A & Dumitrascu. Psychological stress and breast cancer incidence: a systematic review. Clujul Medical. 2018; 91(1): 18-26.
Rock CL, Thomson C, Gansler T, et al. American Cancer Society guideline for diet and physical activity for cancer prevention. CA: A Cancer Journal for Clinicians. 2020;70(4). doi:10.3322/caac.21591. Accessed at https://onlinelibrary.wiley.com/doi/full/10.3322/caac.21591 on June 9, 2020.
Saslow D, Andrews KS, Manassaram-Baptiste D, et al. Human papillomavirus vaccination 2020 guideline update: American Cancer Society guideline adaptation. CA Cancer J Clin. 2020; DOI: 10.3322/caac.21616.
Soung NK & Kim BY. Psychological stress and cancer. J Anal Sci Technol. 2015: 6, 30.
Last Revised: November 3, 2020
American Cancer Society medical information is copyrighted material. For reprint requests, please see our Content Usage Policy.
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