PROBIOTICS: THE FUTURE OF PREVENTATIVE MEDICINE
Joe Zhang
Writer’s comment: I
came up with my paper while sitting on a moss covered bench under a
huge oak tree as brown leaves fell about my head and lady bugs landed
on my notepad. My instructions from Dr. Boe were as follows: “You must
write something that people would want to read instead of being forced
to.” After much thought and frustration, I remembered something my
friend’s brother had said about how germs in hospitals are not able to
survive in the outside world. Through some strange epiphany involving
dirt, wind, and my hospital internships, I decided that this topic was
definitely interesting and meshed well with my initial intentions of
writing about health care. To fill in some of the gaps in the research,
I used myself as a test subject and tried out some of the mentioned
products to develop a personal perspective on the subject. I based my
essay structure mostly on Dr. Mann’s Microbiology 102 class lectures
and added some touches to make the article more appealing to the
average layperson. With this paper, I wish to show that a scientific
essayneed not always be academic sounding or incomprehensible to
scientific outsiders.
—Joe Zhang
Instructor’s comment: I knew Joe Zhang’s
probiotics article was going to be a success when at dinner the evening
after reading a draft of it, I entertained my wife and daughter by
summarizing it. Not only was the subject interesting enough to make me
want to talk about it at dinner, but the article was written well
enough to stick in my memory. I was delighted with Joe’s writing
throughout the course, and especially by how he was unwilling to settle
for the excellent early drafts he wrote. He was willing to labor over
his sentences the way real writers often labor over them, turning them
this way and that way, over and over again, until he either had them
just right or was about to go crazy. I love how “Probiotics” uses a
dramatic first person scene as the lead, then gives us the scientific
background, quotes from various authorities, and even consumer advice.
I often liken feature article writing to making a salad or a soup: the
more you have to throw in, the better.
—John Boe, English Department
Sunday morning. I wake up,
rub my eyes, belch a few times, and stare vacantly at the permanent
pile of laundry on the floor. A bottle of juice, left over from two
nights ago, sits on my table accompanied by some Oreo cookie wrappings.
A Chinese takeout box lies on the floor with a pair of chopsticks
sticking up like a child in a communist classroom with something to
say. Dozens of CD’s, action figures, a fruit cake, and some old
homework lazily recline against a big pile of something that
blocks access to the closet. Yep, this room is a mess. Germs are
everywhere, bacteria growing out of control, and one human waking up
from too little sleep. Fortunately, the cleaning crew has little to do
because this room is intentionally kept dirty.
Instead of causing disease, most of the bacteria in this room actually
help defend humans against sickness. Since I keep the room messy and
covered with bacteria, new pathogens will not be able to gain a
foothold. Scientists call this way of fighting illness with bacteria
“probiotics.”
History
Probiotics is not new. Louis Pasteur of France identified the first probiotic bacteria, Lactobacillus,
in the 1850s. This bacterium was found to occur naturally in yogurt and
improved the health of people who ate it. Today, any bacteria with
health promoting benefits are referred to as probiotic bacteria.
Élie Metchnikoff, a Nobel Prize winning Russian biologist working under
Pasteur in the 1860s, suggested that the body produced harmful
chemicals as a byproduct of digestion. These chemicals ultimately led
to old age and disease. According to Metchnikoff, eating acid-producing
bacteria that eliminate the harmful chemicals can extend the human life
span to some one hundred and fifty years. Science has now proven that
ingested toxins can indeed cause disease, and that certain strains of
bacteria in the gut can neutralize these toxins.
Dr. Henry Tissier discovered the probiotic strain, Bifidobacteria, in 1900. Dr. Tissier was the first person to attempt using bacteria to treat intestinal diseases. By the 1920s, Lactobacillus acidophilus
was successfully used by the United States to treat diarrhea and
constipation. Unfortunately, keeping bacteria alive long enough to be
sold to the mass public was impossible in 1930, and soon probiotics
faded from public interest.
With the advent of improved refrigeration, the Japanese food company,
Yakult Honsha, became the first to commercialize the sale of live
bacteria. In 1955, the company began using Lactobacillus casei strain Shirota,
in the milk product “Yakult.” (The bacterium is named after Dr. Shirota
who discovered it in 1935.)Yakult, now sold in seventeen countries,
guarantees at least six billion live bacteria in every sixty-five
milliliter bottle.
In the 1960s, probiotics became a popular cure for minor aliments among
the hippy generation. Dr. John Boe, lecturer at UC Davis, recounts the
era: “We used to make our own yogurt in a big metal pot with live
bacteria like Lactobacillus acidophilus right at home. When you came down with stomach flu, you would eat the yogurt and replenish the bacteria in your body.”
Today, antibiotics are no longer thought of as a cure all. Many strains
of pathogens are developing immunity to even the newest drugs. To
continue the war on disease, doctors are now enlisting probiotic
bacteria to combat everything from parasites to cancer. Probiotics
represent a solution that is cheap, easy to produce, has no side
effects, and is helpful against many sorts of infection.
How Probiotics Work
The average human body is home to about three pounds of living
bacteria. Over four hundred species, numbering over one hundred
trillion individual bacteria live in the gut alone. We live in
symbiosis with these bacteria by giving them a safe, warm, and wet
place to live. These bacteria, in turn, fight invading microorganisms,
break up fats, destroy cholesterol, alleviate food allergies, dissolve
cancer-causing agents, remove blood toxins, and even produce essential
vitamins.
The bacteria survive mostly in our intestines, lungs, and
on our skin, eating the things that are harmful to us. When we are
invaded by disease-causing bacteria or fungi, the probiotic bacteria
eliminate the pathogens by what is called competitive exclusion.
This term means that friendly bacteria grow to cover all available area
in our bodies so any invaders cannot find enough food or space to grow.
Another way that probiotic bacteria protect against invasion is by
producing acids that interfere with the growth and development of many
germs such as Salmonella and the fungus, Candida.
A few kinds of probiotic bacteria actually produce antibiotics and
bacteriocins, proteins made by bacteria specifically to kill other
bacteria. These chemicals are designed by the bacteria to destroy
invading pathogens and are often far more effective in doing so than
even the newest drugs developed by humans.
Probiotics and Health
Natasha Trenev, author of Probiotics: Nature’s Internal Healers,
describes how when a baby passes through the birth canal, the mother’s
internal bacterial colonies are smeared onto the baby. Most of the
bacteria transferred to the baby belong to the probiotic family Bifidobacteria. The mother’s bacteria coat the baby from head to toe in a protective sheath against germs. Bifidobacteria also stimulate the immune system, colonize the baby’s gut, and help the infant to gain weight by assisting in food breakdown.
Ever since the development of antibiotics, allergies and asthma cases
have increased sevenfold in the United States. Current theory lays most
of the blame on the destruction of friendly bacteria when antibiotics
are administered. During infancy, the immune system learns to identify
harmful substances and organisms. Most of these substances turn out to
be bacteria.
When antibiotics kill all the good and bad bacteria indiscriminately,
the immune system runs out of targets and begins to misidentify
normally harmless substances, such as flower pollen, as potential
threats to the body. Improper immune response to harmless substances is
the cause of allergy for millions of people.
Along with newborns, adults also suffer from antibiotic treatment. The
bacterial shield in the body is destroyed and people become far more
susceptible to infection after taking antibiotics.
Probiotic bacteria in the body respond according to the body’s actions.
Excessive alcohol, sugar, radiation, chlorine, and antacids will
decrease the effectiveness of probiotic bacteria. Stress also changes
the body’s internal chemistry, harming the good bacteria while
promoting the growth of harmful pathogens.
The bacteria in the gut are also tuned to ethnicity. Depending on what
you eat, the different bacteria in your stomach will behave
differently. For instance, an Asian person’s gut bacteria normally
break down rice and Asian foods. If the Asian person suddenly changed
to a western diet with heavy meats, his gut bacteria would not function
well. Because of bacteria-food incompatibability, an immigrant will
often experience various digestive problems such as diarrhea, bloating,
malnourishment, and higher rates of cancer.
Curiously, the Eskimo diet, consisting of mostly whale fats and
cholesterol, does not cause heart disease or cancer in Eskimos. The
bacteria in the Eskimo gut are thought to be responsible for breaking
cholesterol down into smaller particles and helping to eliminate fats.
When isolated, the bacteria responsible for Eskimo health can be
transferred to other people, becoming a cure for excess fat intake.
Buying Probiotics
The easiest way to use probiotics is to take a pill. And the most
important aspect of buying a probiotic pill is checking for the strain
of bacteria used. The following chart lists some of the most popular
species found in local stores. (The bacteria not proven to colonize
still showed beneficial effects simply by passing through the body.)
Bacterium
Able to colonize
Use
Lactobacillus acidophilus
Unknown
Lowers blood cholesterol
Lactobacillus casei strain Shirota
Yes
Helps gastrointestinal ailments
Lactobacillus casei GG
Yes
Fights intestinal diseases
Lactobacillus plantarum 229v
Yes
Improves cholesterol levels
Lactobacillus reuteri
Yes
Cures diarrhea in children
Lactobacillus rhamnosus
Yes
Fights viruses and colon cancer
Bifidobacteria longum
Yes
Degrades cancer-causing nitrates
Bifidobacteria bifidum
Yes
Fights ulcers and colon cancer
Prices for supplements range from four dollars to forty dollars with an
average around nine dollars for a month-long supply. Most of the
cheaper supplements contain only Lactobacillus acidophilus mixed with calcium and preserving agents. The expensive brands sell the new strains such as Lactobacillus casei GG
or a combination of up to fourteen different strains of probiotic
bacteria. Some brands advertise themselves as a super-probiotic, using
the name “Homeostatic Soil Organism” (HSO). HSO is just a fancy way of
saying probiotic bacteria. The base ingredients are actually still the
same bacteria with perhaps a few new additions.
A good brand of probiotic supplement must show the following: an
expiration date, the type of bacteria sold, and the number of Colony
Forming Units (CFU) in each serving. The CFU is an indicator of how
many live bacteria will survive digestion and be of practical use.
After opening, the bottle of supplements must be capped tightly and
should be refrigerated to help keep the bacteria from dying.
Normal low dosage is approximately one hundred million to five hundred
million CFU and is recommended for most people. Medium dose is anywhere
from one billion to ten billion CFU. People under a lot of stress or
are recovering from an illness should take a medium dose. For seriously
sick people, doctors may recommend as high as twenty times the medium
dose.
Unlike most other drugs, probiotic bacteria do not cause overdose
problems. Excess bacteria will simply be passed through the feces. The
first week of treatment with probiotics will cause thirst and gas as
the bacteria clean up the insides of the intestines. Beneficial
effects, such as decreased fatigue, can be felt as early as the day
after initial treatment. If enough colonies are established, the
bacteria may stay effective inside the body for the rest of the
person’s life.
Ongoing research is still discovering and creating new super strains of
probiotic bacteria. Dr. Shahani, researcher at the University of
Nebraska, recently discovered that the super strain Lactobacillus acidophilus DDS-1 produces antibiotics effective against more pathogens than any other probiotic. Unfortunately, L. acidophilus DDS-1, and many other strains are still under development and not yet available to the public.
How to Practice Probiotic Living
Aside from spending money on expensive supplements, there are cheaper
ways to incorporate friendly bacteria into everyday life. Eliminating
all the antibacterial cleaners around the house will prevent antibiotic
resistance in pathogens. Regular soap and water works just fine for
cleaning everything from dishes to hands. The body’s immune system
needs to be challenged and exercised often to maintain peak
performance. Allowing the immune system to react to a few bacteria is
actually a good thing.
Going to public places such as hospitals, libraries, restaurants, or
schools exposes the body to many foreign pathogens. By keeping the
house a bit messier, normal house bacteria, harmless to most humans,
can grow more and crowd out any new invaders from outside the home.
Species of house bacteria differ for every individual home and person.
A house in India will possess a very different set of bacteria than a
home in America. Occupants of the home are immune to their own bacteria
but visitors, especially from overseas, might not be able to tolerate
the bacteria as well.
Some normal house bacteria can become pathogenic in large enough
quantities, but most people become immune to their own house bacteria
after living in a place for a long time. The quantity of normal house
bacteria needed to make a healthy person with immunity sick is
extremely high. Clean up the house if illness develops, visitors come
by, or if car keys become lost too often.
Instead of introducing new bacteria, human breast milk has growth
factors meant to support the bacteria already inside of babies. The
most common type of growth factor is called Fructo-oligosaccharides
(FOS), which is a sugar that cannot be digested by humans, and feeds
the probiotic bacteria. FOS and other bacteria specific nourishments
are called prebiotics. By eating foods with prebiotic qualities such as
onions, garlic, asparagus, bananas, tomatoes, wheat, and Jerusalem
artichokes, the bacteria in the body can easily grow to healthy levels
without the need to take probiotic supplements.
The next time someone comments on the big pile of laundry on the floor,
I can tell them that, yes, the pile can indeed trip any burglars that
come in the night. And then I will add that I am also looking out for
my health by living a probiotic lifestyle. As Dr. Michael McCann, MD,
physician and researcher, puts it, “Probiotics will be to medicine in
the twenty-first century as antibiotics and microbiology were in the
twentieth century.”
References
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2. Wolf BW, et al. “Safety and tolerance of Lactobacillus reuteri in healthy adult male subjects.” Microbial Ecology in Health and Disease: 41-50. 1995.
3. Shornikova AV, et al. “Lactobacillus reuteri as a therapeutic agent in acute diarrhea in young children.” Journal of Pediatric Gastroenterology and Nutrition volume 24: 399-404. 1997.
4. Goldin BR, et al. “Survival of Lactobacillus species (strain GG) in human gastrointestinal tract.” Digestive Diseases and Sciences volume 37:121-128 1987.
5. Yuki N, et al. “Survival of a probiotic, Lactobacillus casei strain Shirota, in the gastrointestinal tract: selective isolation from feces and identification using monoclonal antibodies.” International Japanese Food Microbiology volume 48: 51-57. April 1999.
6. Johansson M.L, et al. “Administration of different
Lactobacillus strains in fermented oatmeal soup: in vivo colonization
of human intestinal mucosa and effect of the indigenous flora.” Applied and Environmental Microbiology volume 59:15-20. January 1993.
7. Majamaa H. and Isolauri E. “Probiotics: a novel approach in the management of food allergy.” Japanese Allergy and Clinical Immunology volume 99:179-85. 1997.
8. Trenev, N. “Probiotics: Nature’s Internal Healers.” Avery Penguin Putnam. New York, NY, September 1998.
9. McCann M. “Prevention of Food Allergy with Probiotics and Pancreatic
Enzymes.” Quote from his lecture at the conference for the
International Center for Interdisciplinary Studies of Immunology
Georgetown University Medical Center. November 1999.
10. Tannock, GW. “Probiotics: A Critical Review” Horizon Scientific Press. New York, NY. January 1999.