You can prevent 43 percent of all cancers by tweaking these lifestyle habits

The key to cancer prevention might very well lie in your hands: According to new research by the American Cancer Society, factors potentially under your control, such as smoking, eating red and processed meats, and physical inactivity, contribute to a sizable chunk of new cancer cases.

In the study, researchers used established cancer risk factors and their relative risk—meaning how much they’re known to up your odds—to estimate the percentages of 26 different types of cancers that can be attributed to them.

The risk factors include the following: cigarette smoking; secondhand smoke exposure; excess body weight; alcohol intake; consumption of red and processed meats; low consumption of fruits and vegetables, fiber, and calcium; physical inactivity; and UV exposure.

They also included six infections which were linked to cancer, including human papillomavirus (HPV)—which is linked to oropharynx cancers—and human immunodeficiency virus (HIV), a major risk factor for Kaposi's sarcoma.

After applying a mathematical formula taking into account relative risks and cancer occurrences, the researchers crunched the numbers, and discovered that 43 percent of all cancer cases in men were attributed to those risk factors.

The most dangerous ones for guys? Cigarette smoking (attributable to 24 percent of all cancer cases), UV radiation exposure (6 percent of all cancer cases), and excess bodyweight (5 percent of all cancer cases). Excessive alcohol consumption and not eating enough fruits and vegetables rounded out the top 5 preventable cancer risk factors for men.

In men, smoking accounted for 84 percent of lung cancers, 75 percent of cancers of the larynx, and 52 percent of cancers of the esophagus. UV radiation was only linked to one cancer, but its effect was staggering—about 95 percent of all cases of melanoma could be attributed to it.

As for excess body weight? That’s likely responsible for about 1 in 3 cases of gallbladder, liver, kidney, and esophageal cancer in men, too.

The viruses played an important role too, though not to the extent of the factors listed above. For instance, HPV caused 0.4 percent of all cancer cases in men—including 38 percent of cases of oropharynx cancers and 59 percent of penile cancers—while HIV caused 0.5 percent, including 89 percent of Kaposi sarcoma, a cancer in the cells that line your lymph or blood vessels.

Of course, viruses like HPV and HIV can be prevented through safe-sex measures, including condoms and dental dams.

As for the other risk factors? The good news is, those factors are well under your control. For instance, take smoking: Within five years after quitting smoking, men’s risk of adenocarcinoma—the most common form of lung cancer—dropped by 52 percent, reaching an 80 percent reduction after another 5 years, a study published in the Journal of Thoracic Oncology found

Plus, many of the other risk factors—poor diet, inactivity, and excess body weight—can be improved with the same simple change: Starting a healthy eating and exercise program. Even losing as little as five percent of your body weight can begin to lower your cancer risk, Graham Colditz, M.D,. chair of the International Agency for Research on Cancer (IARC) told us in the past.

Additional reporting by Elizabeth Millard.