Carcinogen is a word that inspires a certain amount of healthy respect and wariness. After all, it designates something that may cause cancer, which most people make every effort to avoid. Many well-known carcinogens, such as tobacco, radon,
plutonium and asbestos, are obvious offenders, but many others are not so obvious.
Navigating the maze of possible carcinogens is no small task, especially as cancer prevention researchers continue to report new behavioral or environmental cancer risk factors.
Is there a menu item that should be avoided at all costs? A superfood for cancer prevention? An electronic device that increases your risk?
Research reveals that up to half of all cancers may be avoided by making lifestyle choices such as eliminating tobacco use,
maintaining a healthy weight, improving diet and limiting sun exposure.
Crafting a healthy diet
When trying to avoid carcinogens in the diet, the multitude of reports linking foods to cancer risk can be overwhelming. Just recently, MD Anderson researchers have contributed several studies to this field.
Their findings (see “Is what we’re eating giving us cancer?”) reveal increased cancer risks associated with eating more sugar, nutrient-poor carbohydrates and meat — especially when charred by cooking. And last year, the World Health Organization (WHO) determined that enough evidence exists to classify processed meats such as bacon, sausage and hot dogs as carcinogens.
Xifeng Wu, M.D., Ph.D., professor of Epidemiology, also discovered that diets with a high glycemic index, defined by nutrient-poor carbohydrates that rapidly increase blood sugar levels, are linked to higher lung cancer risk in certain
Peiying Yang, Ph.D., assistant professor of Integrative Medicine Research, and Lorenzo Cohen, Ph.D., professor of Palliative, Rehabilitation & Integrative Medicine, determined that fructose increased the risk of breast cancer and
metastasis in laboratory mice.
Despite these reports, avoiding meat, carbs and sugar altogether isn’t the only answer, says Carrie Daniel-MacDougall, Ph.D., assistant professor of Epidemiology.
”Some foods thought of as vices may actually be good for you when consumed in moderation. For example, coffee, wine and chocolate have components rich in phytochemicals that seem to be cancer-reducing,” Daniel-MacDougall points out.
“On the other side of the coin, there may be concerns about each,” she cautions.
“For example, excess alcohol may cause several types of cancer and other diseases.”
Daniel-MacDougall explains it’s not wise to make sweeping judgments about individual foods. Instead, people should practice moderation and understand how foods fit into overall dietary habits.
“It’s a delicate balance of a lot of different things,” she says. “It’s just like a financial portfolio, you don’t want to put all of your eggs in one basket — you want to diversify.”
To minimize cancer risk, MD Anderson and the American Institute for Cancer Research (AICR) recommend eating more fruits, vegetables and whole grains; limiting red meat, alcohol and salty foods; and avoiding sugary drinks. The AICR also suggests maintaining a healthy weight and getting regular exercise.
Minimizing harmful exposure
People are constantly exposed to environmental health hazards such as pollution, radiation and chemicals. Some of these are harmful; others are harmless.
It’s important to separate fact from fiction, she says.
Some chemicals found in everyday items are incorrectly labeled as carcinogens. Bisphenol-A (BPA) is found in hard plastics and food containers and may be linked to early childhood development problems. But there isn’t conclusive evidence to suggest that it causes cancers, Bevers says.
Anecdotal evidence suggests chemicals found in deodorants or even sunscreens may be carcinogens. Once again, Bevers says there is no data to back this up. In fact, not using sunscreen is far more harmful, she explains.
Excessive exposure to ultraviolet (UV) radiation is a major risk factor for all types of skin cancer, Bevers says.
“People should practice sun safety outdoors and avoid ultraviolet tanning beds,” she advises. “Especially when young.”
Other forms of radiation are emitted by cell phones and microwaves, and some people worry they cause cancer. Their concern is unnecessary, says Bevers.
“Both the National Cancer Institute and WHO advise there isn’t enough evidence to label cell phones as a carcinogen,” she says. “As for microwaves, unless you’re crawling inside, you’re well shielded from any radiation.”
An additional source of radiation comes from mammograms and low-dose lung CT scans. Could it be that cancer screening itself could increase your cancer risk?
Bevers is asked about mammogram radiation daily. She explains that both imaging tests produce relatively low doses of radiation. Most people undergoing lung screenings have been heavy smokers all their lives and are already at an increased risk for lung cancer.
“More women will die of breast cancer by not getting a mammogram than from the exceedingly rare and unlikely development of a cancer due to the radiation exposure from a mammogram,” says Bevers.
For the best approach to lowering cancer risk, Bevers recommends maintaining a healthy lifestyle that focuses on avoiding major risk factors such as tobacco use, an unhealthy diet and a sedentary way of life.