This is a FACT.
According to researchers at the University of Southern California, fasting regenerates the immune system, both by preventing immune system damage and by stimulating the production of hematopoietic stem cells that boost immunity. Published in the journal Cell Stem Cell, the recent study showed that fasting for two to four days over a six-month period destroyed aged and damaged immune cells, a finding that not only applies to healthy individuals looking to strengthen their immune systems, but also shows promising potential for enhancing chemotherapy tolerance and treating immune system deficiencies, including autoimmune diseases.
According to USC researchers, when the body thinks it’s starving, it conserves energy by burning through stores of fat, ketones, and glucose. It also recycles immune cells that have been damaged. Testing on both mice and humans in a Phase 1 clinical trial, scientists discovered that fasting decreased the number and size of white blood cells. After eating 72 hours later, white blood cell counts recovered stronger than ever. When white blood cells are depleted, stem cell regeneration and immune system cell production increase.
In mice, the fasting “flipped a regenerative switch” and changed the signaling pathways for hematopoietic stem cells that help the generation of blood and immune systems. In humans, fasting exhibited a protective benefit, helping to defend against toxicity when fasting 72 hours before chemotherapy.
Prolonged fasting periods also decreased levels of the enzyme PKA. Prior research has shown that PKA reduction helps stimulate stem cell self-renewal and extends longevity in simple organisms. Fasting has also been shown to decrease levels of the growth-factor hormone IGF-1, which has been tied to aging, tumor protection, and cancer risk.