hundred trillion microbes that live within
us. And to be clear, these microbes
play a pivotal role in determining our
health destiny. Recently, Drs. Erica and
Justin Sonnenburg from the Department
of Microbiology at Stanford University
conducted a fascinating study. They used
“humanized” laboratory mice, meaning mice
that had been born without any gut bacteria
and were then inoculated with bacteria
from healthy humans. The researchers
studied the effects of dietary changes
on the diversity of the bacterial species in
these animals.
They found that when the animals were
deprived of prebiotic fiber, the level of
diversity dropped quickly and dramatically.
However, they also showed that once
prebiotic fiber was introduced into the diet,
the level of diversity of the gut organisms
significantly improved. Even more
compelling was their finding that when
they repeated this experiment over four
generations, the level of bacterial diversity
continued to worsen. And even when
prebiotic fiber was given, there was less
and less recovery. The authors concluded
that, after several generations, some
bacterial species actually became
extinct, hence the title of the study:
Diet-induced extinctions in the gut
microbiota compound over generations.
There is so much being written these
days about the importance of probiotics
for health and wellness, and a lot
of emphasis is being placed on looking
at specific bacterial species in terms
of their particular effects on our
physiology. But what is really exciting
is the incredible explosion of research
focusing on the long-neglected health
benefits of prebiotic fiber. We know
that nurturing our probiotic bacterial
friends—by giving them healthy dosages
of prebiotic fiber—allows them to
do so many of the things that they
do to enhance our health, such as
manufacturing vitamins and balancing
immunity. And this new research,
showing how critical prebiotic fiber
is in terms of maintaining and even
reclaiming bacterial diversity, adds
so much to our appreciation of how
important a role prebiotic fiber plays in
paving the way for a healthy future.
While the Sonnenburgs demonstrated
that reduction of dietary prebiotic fiber
has a profound and detrimental effect
on the bacteria by reducing diversity,
the up side is that they clearly showed
that when prebiotic fiber is reintroduced
into the diet, diversity can recover.
I believe there is some highly empowering
information in this research. We can pretty
well assume that our diets are not ideal
in terms of nurturing diversity of our
gut bacteria. That said, it certainly
makes sense to do everything you can
to enhance the amount of prebiotic
fiber that you consume on a daily basis.
Foods rich in prebiotic fiber include
jicama (Mexican yam), dandelion greens,
onions, garlic, asparagus, chicory root,
cashews, pistachios, lentils, kidney beans
David Perlmutter, M.D., Board Certified
Neurologist, #1 New York Times
Best-Selling Author & Fellow of the
American College
and Jerusalem artichoke. These days,
prebiotic fiber is available as a nutritional
supplement. Some of the best sources
of prebiotic fiber include acacia gum and
baobab fruit, and prebiotic supplements
made from these sources are widely
available in health food stores and online.
So, remember that prebiotic fiber
enhances gut bacterial diversity. And it is
this diversity that can redirect your health
destiny for the better.
Foods rich in prebiotic fiber
include jicama (Mexican yam),
dandelion greens, onions,
garlic, asparagus, chicory root,
cashews, pistachios, lentils,
kidney beans and Jerusalem
artichoke.
Vol 28 • Extraordinary Health ™ 25