As pointed out in past TotalHealth articles, many
fungi and bacteria found in foods are beneficial
to health. Whether one is discussing breads,
cheeses, fermented tofu, wines, yoghurt,
sauerkraut, kimchi or a number of other items,
very often it turns out that traditional cooking and preserving
techniques involving fungi and bacteria offer many benefits that
are lost with modern alternatives.
This having been said, a major benefit of modern food
science is the ability to supply beneficial bacteria in concentrated
forms. The following discussion is intended to answer questions
regarding the class of dietary supplements referred to as
probiotics. Readers who wonder why some products have single
strains and others offer many, why there often are numbers
or other designations after Latin names of the bacteria, what
benefits might be expected and how soon, etc., should read on.
The species and strains mentioned happen to be ones with which
the author is most familiar.
Do different probiotic strains affect the body in different ways?
Do people benefit from having more of one strain than another?
The human gut consists of a series of microenvironments.
Except for the stomach and the upper two thirds of the small
intestine, there are differing bacteria and ratios of bacteria
in each of these areas, starting with the mouth. In fact, the
human gastrointestinal tract contains a large and diverse
population of microorganisms—over 800 different bacterial
species comprising nearly 100 trillion living organisms.
The composition of this gut flora varies among individuals
depending on diet, age, medication (antibiotics), stress, and
physiological conditions. Not surprisingly, different probiotics
perform different functions and offer different benefits. One big
divide, of course, is between the two most important groups
of typical probiotic bacterial species, Lactobacilli, found mostly
in the lower small intestine and upper large intestine, and
Bifidobacteria, found mostly in the large intestine, i.e., the areas
of lower pH (meaning more acidic).
Broadly speaking, the Lactobacilli act on sugars and starches
to create lactic acid, among other things. For instance, L.
acidophilus La-14 (La-14 indicates the strain within the particular
species) assists in breaking down lactose (milk sugar) and 15
other carbohydrates and this may improve digestion of dairy
products by those individuals who are lactose intolerant.
Clinical trials have shown that this strain may improve
immune response and bowel regularity. It works especially
well in conjunction with another bacteria strain, L. rhamnosus
R0011. Interestingly, L. rhamnosus R0011 in conjunction with L.
helveticus R0052 in humans enhances the eradication of H. pylori
(a cause of stomach ulcers) when ingested in combination with
conventional medical treatment.
Bifidobacteria, especially such as B. longum BB536 (Morinaga
strain), have been shown to colonize the intestine, stimulate
immune response, and promote the growth of other beneficial
bacteria. BB536 also decreased the incidence of influenza in
seniors in trials. Blood analysis showed significantly higher
bactericidal activity of neutrophils and higher NK cell activity at
the fifth week of administration compared to pre-administration.
There has also been evidence reported that suggests BB536 can
help modulate allergies and possess antiallergenic effects. Even
more recent research is looking at the benefits of this strain in
the areas of brain inflammation and dementia.
The finding that certain strains of probiotics reduce
excessive inflammation by means of modulation of immune
and other responses via the gut is one of the major advances in
the knowledge of probiotics in recent years.
Inasmuch as different probiotic species and different
strains of the same species often provide different and distinct
benefits and also often interact to lead to yet other results,
there are good reasons for supplementing with more than
one strain and/or species (I refer loosely and not entirely
scientifically to "species" here to distinguish also, for instance,
Saccharomyces boulardii, which is not another bacterial strain,
but instead a probiotic yeast). Similarly, different supplemental
probiotics may be more to be desired at certain ages or under
particular conditions. No single strain can easily fulfill all these
requirements. A mixture of species, therefore, is usually most
suitable for supplementation. The most desirable properties of
a good probiotic are:
- Compatibility among the strains
- Ability to survive passage through the digestive tract
- Stability under normal gastric conditions
- Resistance to bile salts
- Adherence to intestinal mucosa
- Colonization of the human intestinal tract and/or extended residence time
- Safety with regard to human use
- Production of natural antimicrobial substances
- Antagonism against unfriendly and putrefactive bacteria
- Stability during storage under normal conditions
When purchasing a probiotic supplement, how many different
strains should be in supplement and are all the strains in equal
parts?
There is no one answer to this question. The probiotic yeast,
Saccharomyces boulardii, typically is supplemented by itself
before, during and immediately after antibiotic treatment, but
otherwise may be supplemented in general with a mixture
with bacterial probiotics. As a rule, it is best to supplement at
least the two primary species of probiotics, Lactobacilli, found
mostly in the lower small intestine and upper large intestine,
and Bifidobacteria, found mostly in the large intestine. Three
to eight species and/or strains is a common number. Keep in
mind that these species and strains must be compatible both in
the delivery format and after administered.
What fibers are effective prebiotics?
Let's start by defining the role of prebiotics. According to
researchers in the field, "Prebiotics are supplements or foods
that contain a nondigestible food ingredient that selectively
stimulates the favorable growth and/or activity of indigenous
probiotic bacteria. Human milk contains substantial
quantities of prebiotics." 1 Some researched prebiotic fibers
include trans-galactooligosaccharide, oligofructose, inulin,
larch arabinogalactin, resistant starch, pectin, beta-glucans,
xylooligosaccharides, and oligofructose-enriched inulin.
Recently, scientists have begun to recognize that a number
of polyphenols have prebiotic properties, although there as
yet is no consensus as to the amounts required for benefits.
For instance, proanthocyanidins and other compounds found
in grape seed and red wine can positively affect gut microbial
health, as can related compounds found in dark/minimally
processed chocolate and in cranberries. This is an emerging
area of knowledge.
What is the importance of pH in digestive health and how can
dietary supplements support a balanced pH?
The degree of acidity or alkalinity of a given region of the gut
can be given as its pH. The stomach should have a very low
pH (relatively acidic) prior to meals, e.g., a pH of 2 or below,
because this is needed to digest proteins and to provide a
protective barrier against bacterial invasion of the rest of the
gastrointestinal tract. A low pH in the stomach also is required
to maintain the tonus of the esophageal sphincter to avoid
"heartburn" and other gastrointestinal reflux conditions. The
upper small intestine may approach a neutral pH of 6 and
slightly above after pancreatic digestive fluids are mixed into
foods coming from the stomach; this higher pH is required
for the digestion of fats and for the actions of pancreatic
enzymes. As foods proceed through the small intestine, the
pH should slowly decrease as a result of bacterial action
producing lactic and other acids. Short-chain fatty acids
produced in the intestines exert a number of health effects.
The return to a lower pH in the large intestine is required to
produce peristalsis to maintain the proper passage of food
through the bowel.
Hydrochloric acid precursor supplements can be taken to
improve the production of gastric acid in the stomach. Betain
HCl commonly is used for this purpose.
How do enzymes, herbs and botanicals affect acute symptoms
like heartburn, indigestion, nausea or diarrhea?
Herbs can help for a variety of reasons. Chamomile is famous
for calming properties and typically is taken as an antispasmodic
and anti-inflammatory. Peppermint, especially the
oil delivered by enteric soft gelatin capsules, is another item
for calming the GI-tract. Type "peppermint irritable bowel"
into PubMed and there will be 60 or more hits. Again, it is an
antispasmodic. Ginger is widely touted—and human trials
confirm this—as being good for several forms of nausea.
Readers of past TotalHealth articles may recall that the Asian
herb/food known as bitter melon, especially in its wild forms,
improves various aspects of gastrointestinal health. (Bitter
melon is best consumed with small amounts of "warming"
herbs such as ginger or turmeric.)
A review published in 2012 concluded, "Amongst the most
important we can find [with digestion-enhancing properties]
[are] ginger, peppermint, aniseed and fennel, citrus fruits,
dandelion and artichoke, melissa and chamomile, but many
more have a significant body of experimental data available."2
Pancreatin, which includes trypsin, amylase and lipase,
is specifically produced by the body to digest proteins,
carbohydrates and fats under the relatively neutral pH
conditions found in the stomach at the end of acid digestion
and, primarily, in the small intestine. What most people do not
realize is that the body tends to conserve digestive enzymes.
Long-term use of digestive enzymes can help increase the
body's own reserves of these enzymes for better digestion.
Although enzymes can help acutely with indigestion, this
may not be the best way of conceptualizing their benefits.
Retailers should try to find ways to highlight the contrast
between treating the symptoms of poor digestion and actually
improving digestion. For instance, as a practical matter, no
one has too much acid in the stomach, so quite obviously
taking proton pump inhibitors makes worse an underlying
condition—too little gastric acid. Blocking acid release may
make gastroesophageal reflux disease (GERD) temporarily less
painful, but it does not address why GERD exists.
How does "cleansing" support digestive health? What is a safe
and effective cleanse?
It is important to distinguish between detoxification and
cleansing approaches. Detoxification programs typically focus
on the liver and involve the endogenous Phase I and Phase
II detoxification systems. Cleansing programs, in contrast,
focus on the large intestine and are based on theories of
autointoxication from partially digested foods, especially meat
and other animal foods, leading to the build-up of mucus and
other wastes in the intestines with the absorption of these
toxins into the blood.
There is a grain of truth to cleansing theories. A
considerable part of the toxins and waste products of the body,
such as spent hormones, are eliminated through the bile and
thus via the stool. Likewise, it certainly is true that a lack of
fiber in the diet and dysbiosis in the gut can lead to toxins being
reabsorbed multiple times before being fully excreted from the
body. These two pieces fit together because in its detoxification
processes, the body binds toxins in a variety of ways, two of
which are glucuronidation and sulfation, and then disposes of
the toxins via the bile. Without adequate fiber, including fiber
that can support the growth of friendly bacteria in the gut,
toxins disposed via the bile can be reabsorbed many times
before eventually being eliminated from the body. Similarly,
without the proper fiber, toxins can influence the health of the
cells lining the large intestine. Especially important in this light
are synbiotics, meaning combinations of prebiotics (such as
fiber) and probiotics that work well together to deliver greater
health benefits.
Nevertheless, many of the claims of cleansing programs
seem suspect. For instance, the large intestine turns over the
cells that make up the intestinal lumen roughly every three days,
so claims of a build-up of impacted fecal matter (as opposed
to constipation, something entirely different) do not match the
evidence.
What can a cleansing program accomplish? First, it can
mark a transition to a new general diet. Consuming more fiber
(soluble, semisoluble and insoluble) is well established to
improve constipation, diverticulosis, some forms of irritable
bowel, and to protect against colorectal cancer. How much is
needed? Most estimates are 20–35 grams per day rather than
the usual American consumption of only 10–15 grams per day.
Some health writers suggest consuming herbal gums such as
frankincense, myrrh and mastic gum during this period.
Second, dysbiosis is a real issue and a turnover in the
make-up of the stool through the addition of fiber and
probiotics—a synbiotic approach—can help to change the
intestinal milieu. Again, constipation, diverticular disease and
forms of inflammatory and irritable bowel can be improved by
this combination approach.
The best reason to undertake a cleanse is to transition
to a diet higher in vegetables, whole grains, legumes and
fiber-rich foods in general. This also should help the system
move to a different make-up of intestinal bacteria. A very
simple way to accomplish this is to add approximately 10
grams of good quality fiber to each meal and, assuming that
one does not have a blocked bile duct, to take supplements
that increase the release of bile. These include gentian, artichoke leaf, chicory root, dandelion
root and yellow dock. At the same time,
a good probiotic should be started to
positively influence the composition of
the bacteria found in the gut. The first
few days of such a cleanse may be a bit
uncomfortable and be characterized by
unusual gas and bloating, but by the
end of one or two weeks things should
stabilize. Higher fiber intake from whole
fruit (not juice), vegetables, legumes
and whole grains should continue.
HOW MANY BACTERIA IS ENOUGH
AND HOW MANY IS TOO MUCH?
Too often the impression is that if one or
two billion colony forming units (CFU)
of a probiotic species is good, then 50 or
100 billion must be better. Research and
real life experience do not always agree
with this! There is a strong argument to
be made that approximately two billion
CFU of any given strain is quite enough for everyday usage if the
species and its strain is, in fact, appropriate for the intended
purpose. Formulas containing multiple species and multiple
strains might supply CFU in the range of 10–15 billion using
this reasoning.
Lactobacillus acidophilus is generally considered safe for most
people. Gas, upset stomach, and diarrhea are potential side
effects in some people (not on antibiotic therapy) who take
more than 1 to 2 billion L. acidophilus CFUs daily.3
Supplement shoppers examining probiotic products need
to keep in mind that there are many more types of desirable
organisms in the gastrointestinal tract than merely Bifidobacilli
and Lactobacilli. For instance, according to Tim Spector,
professor of genetic epidemiology at Kings College London and
director of the British Gut Microbiome project, a "healthy gut is
like a perfect English garden. You've got a diversity of microbes
of all types, all living together and feeding off each other's by
products—nothing is wasted."4
Overloading the GI-tract with huge numbers of probiotic
bacteria can crowd out the diversity of bacteria that should
be found in the gut. The result can be so-called "cleansing"
episodes of either or both diarrhea and constipation. Moreover,
excess supplementation or supplementation with probiotic
strains that do not match a person's constitution, rather than
addressing the issues of gas and bloating, actually can increase
these. If a probiotic supplement program still continues to
cause gas and bloating after two weeks, a different source of
probiotics may be found to be more appropriate.
Finally, do not overlook the fact that actual food sources of
probiotics often are the best sources. This means real cheeses
with live cultures, live yoghurt, real rather than artificially soured
sauerkraut, traditionally prepared kimchi and other Asian
soured vegetables, traditionally prepared and preserved pickles
(all of these will be in the refrigeration section of the store), live
sour creams and sour milks, naturally yeast-leavened breads
made the traditional way, and so forth and so on. Among other
benefits, these foods not only often are more nutritious, but
also simply generally taste better.
References:
- Pediatrics. 2010 Dec;126(6):1217–31.)
- Int J Food Sci Nutr. 2012 Mar;63 Suppl 1:82–9.)
- http://umm.edu/health/medical/altmedsupplement/lactobacillus-acidophilus
- http://www.foodmanufacture.co.uk/Ingredients/Gut-health-governs-obesity-immune-response-and-moods
