Exercise boosts immunity in breast cancer survivors, new study finds
While chemotherapy is typically an essential treatment for breast cancer it can dampen an individual’s natural immunity, but new research has found moderate exercise can offer protection against this effect.
The study, published in the journal Brain, Behavior, and Immunity, was conducted by researchers at Ohio State University. Authors of the study assessed participants’ immune response to a typhoid vaccine, which was used to stimulate the immune system.
Researchers evaluated 158 breast cancer survivors ages 36 to 78. They assessed the women for central obesity based on abdominal fat composition and cardiorespiratory fitness level based on their maximum oxygen consumption while riding a stationary bike.
Participants received either the vaccine or placebo over the course of two visits. According to the study, the vaccine produced a significantly higher inflammatory response than the placebo. To gauge the participants’ natural immune response in the seven and a half hours after the vaccination, researchers measured levels of two pro-inflammatory proteins, IL-6 and IL-1Ra, and white blood cells in blood draws taken every 90 minutes and compared them to pre-vaccination levels. While all study participants produced the expected signs of inflammation after receiving the vaccine, three conditions led to a smaller response, according to the study: previous chemo treatment, greater abdominal obesity or belly fat, and a low fitness level.
After controlling for participants’ baseline differences in inflammatory markers, the results showed past chemo treatment, greater abdominal obesity, and lower fitness were associated with lower IL-6 and white blood cell responses. Prior chemo had the strongest effect – generating 44 percent and 35 percent lower levels of IL-6 and white blood cells, respectively, than levels produced by participants who did not receive chemo. This effect was consistent, regardless of how long ago the women had undergone treatment.
Results also showed that a fitness level just slightly above the average increased IL-6 and the white blood cell count by at least 33 percent.
“The paper gives us more data in terms of why cancer survivors may have additional risks,” said lead author Janice Kiecolt-Glaser, PhD, director of the Institute for Behavioral Medicine Research, professor of psychiatry in the College of Medicine and a member of the Comprehensive Cancer Center at Ohio State in a statement. “And the findings send a clear message of just how important physical activity and minimizing belly fat is for robust immune function among breast cancer survivors, and particularly for those who received chemotherapy.”