You probably understand intuitively the link between stress and the immune system. After all, how many times have you come down with a cold shortly after an episode of high stress? Now imagine what your body goes through when exposed to stress over years. Humans evolved to deal with temporary and passing stress, such as the stress of finding food, water, and shelter. These are quite different from the constant stresses of modern life, from financial pressures and deadlines to relationship difficulties and nonstop news.
Substantial evidence suggests that exposure to chronic stress increases rates of cancer development and growth. New research indicates that stress can cause permanent changes to genes, including those that perform key controls in the cancer process.
Once a tumor has developed, stress hormones can make things worse by:
• Increasing tumor growth rates, tumor cell invasiveness, metastatic activity, and tumor blood vessel growth
• Suppressing natural killer (NK) cell activity
• Reducing effects of chemotherapy on tumor cell apoptosis (cell death)
Why Stress Management Matters:
Evidence linking chronic stress, immunity, and cancer is mounting. An important study in 2008 found that stress was associated with higher cancer incidence in initially healthy populations (6-21% increased risk) and higher risk of dying of cancer (29-133% increased risk). Conversely, one study that followed 227 breast cancer patients over 11 years found that women who received stress-reduction support had a 59% reduced risk of dying from breast cancer.
A cancer diagnosis itself causes harmful stress:
In one study, investigators found that for 6,500 adults who survived childhood cancers, 9% (nearly 600 individuals) reported signs and symptoms consistent with PTSD. Further complicating this picture, stress often leads to high-risk behaviors, such as smoking and excessive alcohol use, poor diet, lack of exercise, and obesity, that increase cancer probability. Stress also disrupts sleep and circadian rhythms, which is linked to an increased incidence and progression of certain cancers.
Learn more about managing stress in our book, “Empowered Against Cancer: Science-Based Strategies To Optimize Your Treatments and Thrive – A Practical Guide.” Available in paperback ($19.99) and Kindle ($9.99) eBook formats. Amazon link: