Why You May Not Be Optimizing Your Cancer Protection

A new American Cancer Society study suggests that you can cut your cancer risk with lifestyle choices way more than by reducing exposure to environmental carcinogens. Yet we tend to fear the environmental threats more, and make the recommended lifestyle changes less. Why? And what do choices that don't match the evidence do to our health?

Three sets of short questions:

• Are you among the millions who try to reduce your risk of getting cancer by avoiding pesticides, radiation, and other suspected environmental carcinogens? Do you spend more on organic food, vitamins and supplements, cosmetics, or household goods in part because they promise to reduce your cancer risk? Does the appeal of “all-natural” on the label feel somehow safer?
• Next, are you among the millions who take many of the actions described above, but regularly consume moderate amounts of alcohol, weigh significantly more than you should, don’t exercise much, don't regularly include fruits and vegetables in your diet, and do eat red or processed meat?
• Finally, do you know that if you change the things in the second paragraph you could cut your risk of developing cancer by 40 to 60 percent, while the most reliable estimates are that the environmental carcinogens referred to in the first paragraph cause, at worst, just 20 to 25 percent of cancers? Lifestyle choices about diet and exercise are vastly more effective at reducing your cancer risk than avoiding all of the environmental bogeymen we've been warned about.

But most people believe, wrongly, that environmental carcinogens—radiation, industrial pollution, pesticides, food additives, artificial sweeteners—are more likely to cause cancer. Understandably. A risk that’s being imposed scares us more than one we take voluntarily. And human-made risks scare us more than risks that seem "natural."

So the environmental movement’s dramatic alarms about plastics and pesticides and radiation are understandable—and, to a degree, laudable. Though they sometimes twist or ignore basic evidence and regularly overplay the threat, warnings about many environmental carcinogens have made our air and water and food safer. But they’ve also led to a fear that doesn't match the facts—a fear that has been significantly magnified by the news media that instinctively know what we fear more and understand that we’ll pay more attention to what we’re more afraid of. Which explains why the threat of environmental carcinogen gets more attention, and resonates more strongly with our instinctive risk-perception psychology, than the cancer-prevention work of the American Cancer Society and the CDC and the National Cancer Institute and many other organizations, which all emphasize the much greater protective value of lifestyle choices.

There are a couple additional psychological factors that help explain why we don’t optimize how we protect ourselves from cancer. First, if a risk comes with enough of a benefit, we’ll take it. Drinking alcohol, eating too much, and sitting on the sofa watching something or playing a video game, give us pleasure. That buzz from wine or beer or liquor feels good. Ice cream and french fries and bacon taste good. It's easier to lie around than run around.

Finally, there is the important factor of "control." If we don' t feel like we can do anything to protect ourselves, we feel more afraid. If we feel empowered to protect ourselves, we feel safer. Cancer still feels like something we can't control once we get it (which is wrong, given the progress we’ve made in treating and even curing many types of the disease), but we do feel like we can control our risk of dying from cancer by screening, finding cancer earlier when the dangerous types are more treatable.

Together, the subjective risk perception factors of “control," of “imposed” and “human-made” risk, and our subconscious risk-benefit analyses, sometimes produce behaviors that feel right but do us more harm than good.

• According to statistics in my book, Curing Cancer-phobia: How Risk, Fear, and Worry Mislead Us, in 2017, 21 million Americans sought the reassurance of screening for cancer even though they were younger or older than the age groups for whom cancer screening is recommended. The problem is—and few people appreciate this—screening does save lives, but it also causes a lot of harm. Many types of screening produce psychologically damaging false positives. Worse, screening often discovers thousands of slow-growing early breast and prostate and thyroid cancers that are “overdiagnosed,"—types of disease that would never go on to kill. But, as frightening as cancer is, most people told they have such forms of the disease choose more aggressive and risky treatment than they clinically require, and tens of thousands of them are seriously harmed, and some even killed, by the treatment, not the cancer.
• Perversely, some of us get a sense of control by avoiding cancer screening, or even by delaying going to the doctor when symptoms develop that could be cancer. So deep is our fear of the disease that many people take control by avoiding finding out they have it, even though they surely know that delay leads to worse outcomes.
• We press our government to control the threat of environmental carcinogens, so we spend vastly more on that threat than we do to reduce other major environmental health threats, like particulate air pollution, that pose as much danger as cancer if not more. We get a sense of control when we press our government to spend billions on the “War on Cancer," and as result, the National Institutes of Health spends three times as much on cancer research and prevention as it does on heart disease, which kills 95,000 more of us each year. We get a sense of control by resisting fluoridation of public drinking water (roughly 25% of U.S. public drinking water supplies are not fluoridated) because some people fear, wrongly, that it causes cancer; by resisting clean nuclear energy (which emits no greenhouse gasses or particulate pollution), or by resisting the installation of cell phone towers or even WiFi transmitters on our home electric meters, all because of excessive cancerphobia of anything connected to the word "radiation."

Cancer is an awful disease that causes great suffering. Most of us have been scarred by it. There are plenty of valid reasons to fear it. But in some ways our cancer fears exceed the facts, and that cancerphobia is dangerous, too. We have to understand the disease better if we want to reduce its toll. And we have to understand the psychology of our cancerphobia to reduce its harms, too.