We all know that too much stress is bad for us. But if you fail to control the stress in your life, could you be encouraging your own cells to malfunction?
Some studies show a link. In 2004, The Lancet Oncology published one that found chronic stress weakens the immune system, which in turn may affect the incidence of virus-associated cancers like Kaposi sarcoma and some lymphomas. In 2006, Nature Reviews Cancer published another study-this time, scientists found that stress releases hormones that can affect DNA repair and regulation of cell growth, reducing the body’s own defenses against cancer. A 24-year study of women in Sweden showed that those who reported high levels of stress, including tension, fear, anxiety, and sleeplessness, were twice as likely to develop breast cancer as those with low levels of stress.
Scientists are quick to point out, however, that more studies need to be done, and that researching the effect of stress on the development of cancer is difficult, as it’s hard to separate it from other factors like smoking, alcohol use, obesity, family history of cancer, etc. Still, many survivors believe stressful events preceded their diagnoses. “I was divorced in 1990 and diagnosed in 1999,” says Mary Morrissey, cancer survivor. “I do think that was the reason for my cancer. I suffered panic attacks and my stress levels were very high.”
“I was stressed out,” says Jim Keifert, survivor. “I know stress caused my cancer.”
Most researchers insist the question is still open. “I have no idea,” says Barbara Anderson, psychology professor at Ohio State University, “and nobody else does, either.” Dr. Helgesson, lead author of the aforementioned Swedish study, agrees. “Although our study does show a significant association between stress and breast cancer, I would emphasize that more research needs to be carried out before it can be said that stress definitely increases risk.”
There is conflicting evidence. For example, a large study done in Denmark looked at the incidence of cancer in over 11,000 parents whose children had cancer-definitely a stressful event. However, the parents had no more cancer than members of the general population.
Part of the reason stress may be so associated with cancer risk is that it used to be believed that the immune system was fighting off cancer cells everyday in the body, and that something happened to weaken it to allow the cancer cells to take hold. However, recent studies have shown that this probably isn’t the case. Mice that were genetically altered to have no functioning immune systems didn’t show huge increases in cancer, and patients with HIV-Aids, who had naturally weakened immune systems, were no more at risk for the majority of cancers that plague the population (though they did show increased risk in viral-related cancers). Now, scientists believe that cancer cells gain the upper hand by using proteins that turn off the immune system’s attack-not because of a weak immune system.
Bottom line: We just don’t know yet if stress actually “causes” cancer. We do know it reduces the effectiveness of the immune system, but how that might translate into cancer is still elusive. “People in high-stress occupations, such as police officers, doctors and firefighters, don’t have higher incidences of cancer than other members of the community,” said Dr. Derek Raghavan, director of the Cleveland Clinic Taussig Cancer Center. “There is folklore that people who are grieving have a higher chance of getting cancer than others. But the data are conflicting, and carefully controlled studies do not support it.”
The good news is that if you are diagnosed, you don’t have to blame yourself for failing to handle stress. Remember that cancer is a very complicated disease with a myriad of causes and unknown reasons for developing. In the meantime, improving your ability to handle stress is definitely good for your health, cancer or not, so join support groups when you need to (they have shown in some studies to help cancer fighters live longer), and consider coping techniques like meditation, massage, journaling, carving out time for personal relaxation, expressing your feelings instead of bottling them up, and focusing on the things you’re grateful for.
What do you think of the stress/cancer connection? Please share your thoughts.
Photo courtesy batdongsankimlong via Flickr.com.
