Therese Bevers, M.D., medical director of the Cancer Prevention Center at MD Anderson Cancer Center
Deborah Capko, M.D., oncological surgeon at Memorial Sloan-Kettering Cancer Center
Johnathan Lancaster, M.D., president of the Moffitt Medical Group at H. Lee Moffitt Cancer Center & Research Institute
Peter Shields, M.D., deputy director of The Ohio State University Comprehensive Cancer Center
Additional info from the National Cancer Institute and the American Lung Association
Smoking1 of 19
Tobacco is responsible for 80 percent of lung cancer deaths in American women and increases your risk for cervical, pancreatic, kidney and oral cancers. Quit now—after 10 years, your risk of dying from lung cancer is cut in half.
Your Age2 of 19
Seventy-seven percent of cancers are diagnosed in people older than 55. The effects of aging on your cells combined with bad behavior and outside factors take their toll. You can't freeze time, but you can adopt healthy habits today.
The Sun's Rays3 of 19
About 65 percent of incidents of the deadliest form of skin cancer—melanoma—are directly caused by UV radiation from the sun. When enjoying the beams, please, sunscreen.
Genetics4 of 19
Yes, genes are powerful, but only 5 to 10 percent of cancers are genetic. And even if you do have a family history, good habits may "turn off" bad genes through the epigenome, a system of DNA-related chemicals. Take that, double helix.
STDs5 of 19
HPV and hepatitis B are linked to certain cancers, and HIV could indirectly raise your risk. Ask your doc about HPV and hepatitis vaccines. (And, P.S., a condom wouldn't hurt.)
Obesity6 of 19
By raising the level of hormones circulating through your body, excess fat seems to create a cozy home for cancer growth. Drop some pounds; lower your risk.
Alcohol7 of 19
Yes, a bit of booze can help your heart and brain. But (sucky-health-fact alert) only one glass a day slightly raises breast cancer risk, and more is worse. Weigh the choices with your M.D.
Diet8 of 19
We love hot dogs and bacon. But truth: Red and processed meats may raise your risk for colorectal cancer. Plus, sugary drinks are so highly associated with obesity that they could indirectly bump up your cancer risk.
Inactivity9 of 19
Getting your heart pumping can lower your chances of getting colon, breast, lung and even endometrial cancer. Aim for 150 moderate minutes or 75 vigorous minutes per week. If you happen to lose weight, even better.
The Pill10 of 19
Birth control with estrogen may lower risk for ovarian and endometrial cancers, but it raises it slightly for breast cancer. When you choose to go off, the risk drops.
Radiation11 of 19
It's unavoidable—even bananas emit a little! And although medical scans do carry dangers, the upside outweighs them; just confirm that tests are truly needed.
Stress12 of 19
In theory, chronic stress could impact immunity and DNA repair, which help fend off cancer. But the science isn't solid. For now, call it one less worry.
Cell Phone13 of 19
Large studies haven't consistently linked phones to cancer. But the tech and our use habits change rapidly, so we can't be sure. A hands-free set could be safer.
Bisphenol A14 of 19
The number is low because the jury is still out. But animal studies have linked BPA—a compound found in some plastic and cans—to an increase in cancer risk. Avoid it when you can.
Sweeteners15 of 19
Pink, blue or yellow packet, there's no solid evidence artificial sweeteners give you cancer. In the 1970s, scary studies were done on lab rats, but the results never translated to humans.
Caffeine16 of 19
Research suggests your morning joe can actually reduce your risk for basal cell carcinoma. Gulp that skim latte without guilt (but easy on the sugar, if you can resist).
Antiperspirant17 of 19
Delete the chain emails: Your roll-on does not seep into your system and cause cancer. And have you heard the one about under-wire bras and cancer? Yeah, also false.
Abortion18 of 19
Abortion does not—we repeat, not—cause cancer. By the way, some states require medical pros to warn you about this made-up risk. So appalling. Ignore, ignore, ignore.