Probiotics Side Effects
Problems, side effects and unsubstantiated
claims are possible with any medicine or food
product, including probiotics. In that a
probiotic is an actual organism, it carries some
unpredictability in terms of how it will react
to the existing or indigenous microbiotica
located in the subject's GI tract. Because
probiotic supplements have significant
components that may not survive the transit
through the gastric system, they carry the
potential of having no effect at all. The
expense of purchasing the product must be
considered carefully, if it delivers minimal
value to the user. Since brand quality varies
significantly among probiotic producers, buyers
are cautioned to research their probiotic
One of the most prolific scholars in the field
of GI tract microflora is Fergus Shanahan of the
National University of Ireland. Shanahan is an
often-quoted source in the discussion of how
probiotics work, and whether their health claims
are justified by hard science. In his 2005
article entitled "Probiotics: Promise, Problems,
and Progress," he cites over forty studies in
the field of gastroenterology and microbiology.
Shanahan is quick to point out that particular
illnesses such as post-antibiotic diarrhea are
very responsive to probiotic treatments.
However, he emphasizes that many of the studies
on humans-- such as the results for Crohn's
disease --have been disappointing. He cites many
examples of brilliant therapeutic potential that
still need a great deal of study prior to
recommending particular probiotics for medicinal
purposes. Shanahan concludes by warning
consumers and clinicians against using products
not backed up by solid science.
That the user may need or expect a definite
medical benefit on a certain timetable may also
be a challenge associated with probiotics. In
many countries, the regulation of probiotic
supplements is not on the basis of a medicine,
but rather, as a food supplement. If patients
seek a dietary supplement instead of a medical
exam, or if they delay a medical exam in order
to attempt self-treatment, there is a chance
that a disease may go undiagnosed and untreated
with dangerous results. With these challenges in
mind, probiotics might be encouraged as one
facet in a patient's health maintenance
strategy. Other facets would include regular
check-ups, proper diet, exercise, and diagnostic
testing whenever a serious medical issue arises.
A variety of cautionary warnings are related to
probiotics, including the following:
- Inactive ingredients of probiotic formulas may
include plant-derived and mineral substances
that are not well-tolerated by the user. Check
labels carefully for these ingredients.
- In double-blind, placebo-controlled studies,
probiotics have not been shown to help with
Crohn's disease, and are not usually recommended
for patients with Crohn's disease (F Shanahan,
- A study conducted for the Dutch Acute
Pancreatitis Study Group, as reported in "The
Lancet" (February 2008) confirmed that
probiotics are not appropriate for the treatment
of this disease. Probiotics have increased
mortality in patients with severe pancreatitis.
If problems with the pancreas are suspected,
probiotics would not be a prudent course of
- Among discussion sites for alternative
medicine, a great deal of anecdotal information
is available, but these are not a substitute for
empirical evidence of therapeutic properties.
- Probiotic users have reported cases of
bloating, gas, and lower abdominal pain when
trying a new formula that they did not introduce
in small incremental stages.
- Excessive drainage syndrome can result from
competing bacterial colonies when a new
probiotic is introduced to the intestine or
colon, according to the alternative medical
therapies promoted by "The Gertonson Institute"
web site. With excessive drainage, probiotic
supplement users occasionally suffer from
dehydration. Intake of adequate liquids and
electrolytes should be encouraged when a
probiotic cleansing regimen is underway.
The European Food Safety Authority (EFSA)
recently rejected 171 of 181 proposals related
to probiotic claims of health benefits. Some
objections of the EFSA in rejecting probiotic
health claims are similar to the issues raised
by Fergus Shanahan:
- International labelling conventions,
standardization, and nomenclature of particular
strains have not been established.
- Quality control measures for the optimum
sources, shelf life, and storage methods of the
bacteria have not been fully investigated.
- Inactive ingredients are not controlled and
classified clearly enough.
- Most individuals have not determined which
microflora are present in high, low or optimum
numbers within their own GI tract, so the
process of trying to supplement particular
populations may involve too much guesswork.
- Since each human family and each individual in
that family carries a different combination of
gut microflora, there may be genetic
propensities for and against certain probiotic
species; more study is needed to see which
groups may benefit from which types of bacteria.
- Whether a particular disease or genetic
propensity is addressed by a particular
probiotic strain cannot reasonably be claimed
unless significant statistical evidence is
- Particular strains shown to have certain
effects need to be better catalogued, with an
official depository source of samples that
maintain consistent genetic traits.
- Genetic tampering with particular probiotic
strains has led to many unofficial sub-species
with unregistered names; misnomers and repeated
names are a threat to the integrity of
well-identified probiotic species.
- Many studies of probiotics to date have not
involved human trials. Lab results and animal
studies cannot always be generalized to results
- Dosing levels and optimum serving sizes,
classified by weight and age, have not yet been
defined or standardized for probiotics.
Extra care should be taken if introducing
probiotics into a child's diet, as adult
products are not usually suitable for juvenile
and infant use. Although probiotics are rarely
reported to create medical damage in the user, a
specific allergy to the ingredients of any food
or supplement is possible. For probiotic
supplement users that are attempting a major
"internal cleansing," on the advice of
alternative medical sources, an incremental
process is recommended where small occasional
doses are tried at first. Trying familiar
strains of bacteria is recommended as a first
stage. A sudden large dose may cause digestive
upset. Using the more traditional advice from
EFSA and Fergus Shanahan, the consumer should
adopt the attitude of "let the buyer beware,"
and conduct significant research on the
reliability and reputation of the company
producing the probiotic, before purchasing or
ingesting anything from that company.
- Marc Besselink MD, Hjalmar van Santvoort MD,
Erik Buskens MD, Marja A Boermeester MD e, et
al. for the Dutch Acute Pancreatitis Study
Group. "Probiotic prophylaxis in predicted
severe acute pancreatitis: a randomised,
double-blind, placebo-controlled trial." The
Lancet, Volume 371, Issue 9613, Pages 651 - 659,
23 February 2008.
- Fergus Shanahan. "Probiotics: Promise,
Problems, and Progress." Alimentary Pharmabiotic
Centre and Department of Medicine, University
College Cork, National University of Ireland,
Cork, Ireland. 2005.
- Chanakira, Bishop. "Are There Probiotics Side
Effects and What Are They?" Articlear.com.
- Gertonson Institute. "Important Information
About Starting Probiotics." Gertonson Web Site.
- Shane Starling. "EFSA Publishes Probiotic
Guidance." The Dairy Reporter, 22-Oct-2009.
complete description of probiotics, along with
groundbreaking recent clinical research
illustrating the many ways probiotics can
prevent disease, can be found in
Probiotics - Protection Against Infection: Using
Nature's Tiny Warriors To Stem Infection,
This new compendium from one of our own site
contributing authors, Dr. Casey Adams, PhD., takes
the confusion out of selecting and supplementing
with probiotics. Referencing over 500 scientific
studies and reports, and with detailed
instructions on how to make your own probiotic
foods, this book is a must for anyone seeking to
understand the power of probiotics, and improve
their immunity and vitality.
for ordering information.
Discover Which Probiotics Can Help You!
to learn more about this
just released, groundbreaking book.