Periodic fasting could help combat "chemotherapy-induced and aging-related" dips in immune system function.
Chemotherapy can significantly deplete immune cells, and even normal aging can be hard on the immune system. Researchers believe fasting every once in a while could combat this, a Cell Press news release reported.
The dietary practice is believed to have the ability to replenish stem cells in the blood.
About one-fifth of cancer-related deaths are believed to be linked to the harmful effects of chemotherapy. The dips in immune system function can cancel out the cancer-fighting effects of the treatment.
There is currently no therapy to combat the harm chemotherapy can have on the immune system, but past research has shown that dietary practices could help.
"We show that prolonged fasting periods cause a major reduction in white blood cell number followed by its replenishment after refeeding," Doctor Valter Longo, of the University of Southern California, said in the news release. "We discovered that this effect, which may have evolved to reduce energy expenditure during periods of starvation, is able to switch stem cells to a mode able to not only regenerate immune cells and reverse the immunosuppression caused by chemotherapy, but also rejuvenate the immune system of old mice."
The researchers observed a protection in white blood cell loss in cancer patients who had fasted for a 72-hour period before receiving platinum-based chemotherapy in a Phase I clinical trial.
The method is believed to work because it reduces levels of "insulin-like growth factor-1 (IGF-1)," the news release reported. This protein has a strong connection to growth and aging.
"We and others are currently testing the effect of fasting-mimicking diets on the protection of patients against chemotherapy's side effects, and we're also testing the role of multiple cycles of a fasting-mimicking diet on the immune system in generally healthy middle-aged and elderly subjects," Dr. Longo said.
