• Cancer

    Consumer Health: Cancer myths vs. facts

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February is National Cancer Prevention Month, which makes this a good time to learn about what does — and does not — cause cancer.

In many cases, what is known about cancer prevention is still evolving. However, it's well-accepted that your lifestyle affects your chances of developing cancer. From your diet and exercise routines to protecting yourself from the sun and avoiding risky behaviors, a few simple lifestyle changes can make a difference in your risk of developing many types of cancer.

However, many claims about what causes cancer may cause you to worry unnecessarily about your health and the health of your family.

Before you panic, take a look at the facts behind these common myths:

Myth: Antiperspirants or deodorants can cause breast cancer.
 No conclusive evidence links the use of underarm antiperspirants or deodorants with breast cancer. Some reports have suggested that these products contain harmful substances such as aluminum compounds and parabens that can be absorbed through the skin or enter the body through nicks caused by shaving, but the evidence to date suggests these products don't cause cancer.

Myth: Microwaving food in plastic containers and wraps releases harmful, cancer-causing substances.
 Plastic containers and wraps labeled as safe for use in the microwave don't pose a threat. You should avoid microwaving plastic containers that were never intended for the microwave, though, such as margarine tubs, takeout containers or whipped topping bowls. Evidence suggests that plastic containers that aren't intended for use in the microwave could melt and potentially leak chemicals into your food.

Myth: People who have cancer shouldn't eat sugar, since it can cause cancer to grow faster.
 More research is needed to understand the relationship between sugar in the diet and cancer. All kinds of cells, including cancer cells, depend on blood sugar for energy. But giving more sugar to cancer cells doesn't make them grow faster. Likewise, depriving cancer cells of sugar doesn't make them grow more slowly.

Evidence suggests that consuming large amounts of sugar is associated with an increased risk of certain cancers, though, including cancer of the uterus, cervix, endometrium, ovary, breast, colon, rectum, esophagus, liver, gallbladder, pancreas, kidney and prostate.

Myth: Cancer is contagious.
 You don't need to avoid someone who has cancer. You can't catch it. It's OK to touch and spend time with someone who has cancer. Your support may never be more valuable.

Though cancer itself isn't contagious, sometimes viruses, which are contagious, can lead to the development of cancer. Examples of viruses that can cause cancer include HPV and hepatitis B or C. Talk to your health care provider about vaccines and other ways to protect yourself from these viruses.

Connect with others talking about preventing cancer and living well with cancer in the Cancer support group on Mayo Clinic Connect, an online patient community moderated by Mayo Clinic.