It’s the first evidence of its kind: prolonged fasting resulting in stem cell-based regeneration of either a bodily organ or system, reported in the journal Cell Stem Cell. Its findings show that cycles of extended fasting protect against immune system damage and also induce immune system regeneration, catalyzing stem cells from dormancy to self-renewal.
For both mice and Phase 1 human clinical trials with chemotherapy patients, long periods of fasting significantly lowered white blood cell counts, and, in mice, the fasting “flipped a regenerative switch,” to promote stem cell-based regeneration of the hematopoietic system. The hematopoietic system is comprised of the blood-making organs, including the bone marrow and lymph nodes.
Corresponding author, Valter Longo, Edna M. Jones Professor of Gerontology and the Biological Sciences at the USC Davis School of Gerontology and director of the USC Longevity Institute, observes, “We could not predict that prolonged fasting would have such a remarkable effect on promoting stem cell-based regeneration of the hematopoietic system.”
Longo explains, “When you starve, the system tries to save energy, and one of the things it can do to save energy is to recycle a lot of the immune cells that are not needed, especially those that may be damaged.” Longo said. “What we started noticing in both our human work and animal work is that the white blood cell count goes down with prolonged fasting. Then when you re-feed, the blood cells come back.”
Then, with each cycle of fasting, the white blood cell depletion caused changes that triggered stem cell-based regeneration of new immune system cells. Prolonged fasting also lowered IGF-1 levels. IGF-1 is a growth-factor hormone that is linked to aging, tumor progression and cancer risk.
Longo continues, adding, “And the good news is that the body got rid of the parts of the system that might be damaged or old, the inefficient parts, during the fasting. Now, if you start with a system heavily damaged by chemotherapy or aging, fasting cycles can generate, literally, a new immune system. We are investigating the possibility that these effects are applicable to many different systems and organs, not just the immune system.”
This is all groundbreaking and truly exciting news, but what are stem cells and what are some of the implications of this study’s findings?
Stem cells are considered the body’s raw materials, since they’re the cells from which all other cells with specialized functions are created. Stem cells are the only cell types which can generate new cell types. Given the proper conditions, stems cells can divide to form what are called daughter cells, which will become new stem cells or specialized cells with a more targeted function, such as blood cells, brain cells, heart muscle or bone cells.
This not only has major possibilities for healthy aging, since the immune system can lose its effectiveness and lead to increased disease susceptibility as people age, but it also indicates possibilities for improved chemotherapy tolerance as well as application for those with immune system issues, including autoimmune disorders.
Of course, any fasting should be performed only under the advice and/or supervision of your healthcare professional.
More studies are or will soon be underway, so stay tuned.
This information is intended for educational and informational purposes only. It should not be used in place of an individual consultation or examination or replace the advice of your health care professional and should not be relied upon to determine diagnosis or course of treatment.