DR JOHN MORGAN

RESEARCH ROUND-UP
Edited by Katie Barnes. Email: katiebarnes@leisuremedia.com
PHOTO: WWW.SHUTTERSTOCK.COM/ALEXANDER PEKOUR
Fasting can help the
body regenerate its
immune system
A groundbreaking study has found that fasting can help regenerate
the immune system and could have a role to play in healthy ageing
A
bstaining from eating for
periods of two to four days
at a time not only helps
to protect the immune
system from damage, but also leads
to cell regeneration, according to a
groundbreaking new piece of research*.
Scientists at the University of
Southern California (USC) in the
US say this is the fi rst time a natural
intervention has been found to trigger
stem cell-based self-renewal of an organ
or system. And the fi ndings could have
major implications for healthy ageing.
As people age, their immune system
declines, making them more susceptible to
disease; being able to prevent or reverse
this process could help prevent illness in
this group. It could also potentially benefi t
those with autoimmune disorders, and
cancer patients whose immune systems
are weakened by chemotherapy.
Flipping the switch
Over a course of six months, the
scientists looked at the impact prolonged
fasting cycles had on mice as well as
patients undergoing chemotherapy. Both
the mice and the people went without
food for two- to four-day periods.
In both cases, not eating initially
lowered the white blood cell counts – the
cells that defend the body against disease
– as the body started getting rid of old
or damaged cells. “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,” explains lead study author
Valter Longo, a professor of gerontology
and biological sciences at USC.
Eventually, however, prolonged
periods of fasting in mice then “fl ipped a
regenerative switch” which kick-started
the stem cells into producing brand
new white blood cells. This essentially
rebooted the whole immune system.
The PKA enzyme
Importantly, the scientists also found
that, when people don’t eat for long
periods, levels of the enzyme PKA are
lowered in the body. In previous studies,
PKA has been linked to the regulation
of stem cell self-renewal and the
potential for one cell to develop into
many different cell types.
“PKA is the key gene that needs to
shut down in order for these stem cells
to switch into regenerative mode,”
clarifi es Longo, who’s also the director
of USC’s Longevity Institute.
“It gives the OK for stem cells to go
ahead and begin proliferating and rebuild
the entire system. And the good news is
that the body got rid of the parts of the
system that might be damaged or old,
the ineffi cient parts, during the fasting.
Now, if you start with a system heavily
damaged by chemotherapy or ageing,
fasting cycles can generate, literally, a
new immune system.”
Additional benefits
Other results from the study, which was
published in the Cell Stem Cell journal in
June, showed that long periods of fasting
lowered levels of IGF-1, a growth
hormone that’s associated with ageing,
tumour progression and cancer risk.
In another pilot clinical trial on a small
group of chemotherapy patients, Longo
discovered that fasting for a 72-hour
period before treatment protected the
body against toxicity.
* Longo, V et al. Prolonged Fasting Reduces IGF-1/PKA to Promote Hematopoietic-Stem-Cell-Based Regeration and Reverse Immunosuppression, Cell Stem Cell, June 2014
66
Read Health Club Management online at healthclubmanagement.co.uk/digital
November/December 2014 © Cybertrek 2014