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.)

        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

1. Walker, M. “Medical Journalist Report of Innovative Biologics: Homeostatic Soil Organisms for One’s Primal Defense.” Townsend Letter for Doctors & Patients: 18-19. February 2001.

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.