From encouraging and protecting gut health  and elimination to reducing inflammation and supporting the immune system, probiotics play many essential roles in our overall health. With the growing interest in healthy living and integrative medicine, the use of beneficial bacteria has become a popular topic. And as research continues to reveal the multiple health benefits of probiotics, many healthcare professionals have begun recommending them for their patients.
What Are Probiotics?
Just what are probiotics? The word probiotics literally means “for life” (from the Latin pro, meaning “for” and the Greek biota, meaning “life”). The official definition of probiotics was amended in 2014 by the International Scientific Association for Probiotics and Prebiotics (ISAPP ) to say, “Live microorganisms that, when administered in adequate amounts, confer a health benefit on the host.” In simpler terms, probiotics are “good” bacteria.
The Bacterial Balancing Act
Before we can discuss the benefits of probiotics, it’s important to understand how bacteria work in our bodies. Here are some interesting facts about bacteria:
- Bacteria can be found pretty much everywhere.
- In humans, these microscopic organisms live on the skin and in mucosa.
- An estimated 500 to 1,000 different species of bacteria inhabit the gut and a similar number live on the skin.
- The bacterial population in humans is so large that bacterial cells outnumber human cells by 10 to 1.
- The vast majority of bacteria in humans can be found in the large intestine.
- Approximately 100 trillion of these microorganisms live in a normal, healthy bowel.
Over the years, bacteria have gotten a lot of negative press. Most people associate bacteria with the four Ds: dirt, disease, death, and decay. While it’s true that some bacteria do cause diseases and even death, the majority of bacteria are actually beneficial to your health.
In reality, only about 10% of bacteria are “bad.” The other 90% are “good” bacteria that aid in food digestion, regulate proper immune function, and defend against disease-causing pathogens.
In order to keep a body healthy, bacteria must maintain a delicate balancing act. It’s the biological version of the classic struggle of good vs. evil. As long as the good bacteria predominate, they can effectively fight off the “evil” or bad bacteria.
However, when the ecology of the gastrointestinal tract becomes disrupted, the good bacteria can no longer flourish in needed numbers and proper balances. It is then that harmful toxin-producing bacteria begin to take over.
Antibiotics: The Good, the Bad and the Ugly
When it comes to disrupting the body’s bacterial balance, one of the biggest culprits is antibiotics. The purpose of antibiotics is to destroy disease-causing bacteria. But if you’re using antibiotic therapy as part of chronic illness treatment, the problem is that antibiotics can’t distinguish good bacteria from bad—so they kill both—and set the stage for Candida overgrowth .
Antibiotics are what you might call a necessary evil. To be sure, they are an important tool for fighting serious disease and can save lives. But they can also cause troublesome side effects like antibiotic-associated diarrhea (AAD). If the good bacteria are not replenished quickly, antibiotics can leave you open to other illnesses. In circumstances where antibiotics may be necessary, probiotics help maintain intestinal health and reduce side effects.
Even if you don’t often take antibiotics, you are still likely to be getting them through your food and water. Giving antibiotics to potential food sources, like cows, swine, chickens and fish, so they will gain weight faster as well as to prevent infection is a common practice. Scientists are also discovering significant levels of antibiotics in our water supplies from a variety of sources. So your body is probably getting a lot more antibiotics than you realize.
History of Probiotics
The concept behind probiotics was first introduced in the early 20th century, when Nobel laureate Elie Metchnikoff, known as the “father of probiotics,” proposed in The Prolongation of Life: Optimistic Studies that ingesting microorganisms could have substantial health benefits for humans. In his milestone book, Dr. Metchnikoff documented what he believed to be a direct link between human longevity and the necessity of maintaining a healthy balance of beneficial microorganisms within the body.
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Although researchers continued to carry on Dr. Metchnikoff’s work, it moved along slowly until the tail end of the 20th century. That’s when we began to see a dramatic increase in probiotic research. The U.S. consumer market, once slow to jump on the probiotics bandwagon, continues to grow rapidly. In general, Europeans consumed a lot of probiotics because they traditionally eat foods like yogurt and sauerkraut that are fermented with bacteria. Likewise, Southeast Asians have historically eaten foods high in probiotics such as kimchi and miso soup.
Additional Probiotic Benefits
Western medicine has a reputation of being reticent when it comes to recognizing the helpfulness of supplements and other natural therapies, but in the case of probiotic benefits, many highly respected medical authorities are acknowledging their positive effects.
Research is ongoing, but there’s promising evidence that probiotics may help:
- Diarrhea, especially after the use of antibiotics
- Vaginal yeast infections and urinary tract infections
- Irritable bowel syndrome (IBS)
- Bladder cancer recurrence
- Treat some intestinal infections
- Eczema-related symptoms in children
- The severity of colds and flu
- Inflammatory disease like ME/CFS, fibromyalgia , Lyme disease, ulcerative colitis, irritable bowel syndrome (IBS), and more.
- Reduce allergies
Probiotics can provide the beneficial bacteria our bodies need to maintain healthy digestion and to counteract some of the side effects of antibiotics. There is also growing evidence that they may provide significant benefits for a number of other health issues, such as helping to reduce inflammation and enhancing proper immune system function. Probiotics are available as single strain (monstrain) or multi-strain supplements. Different strains may work better for different people, but the human gut contains several hundred different microbe species known as the microbiome—so you may find that probiotics work best for the body to consume multiple probiotic strains and species.
This article was first published on ProHealth.com on December 23, 2011 and was updated on May 16, 2019.
Karen Lee Richards is ProHealth’s Editor-in-Chief. A fibromyalgia patient herself, she co-founded the nonprofit organization now known as the National Fibromyalgia Association (NFA) in 1997 and served as its vice-president for eight years. She was also the executive editor of Fibromyalgia AWARE magazine. After leaving the NFA, Karen served as the Guide to Fibromyalgia and Chronic Fatigue Syndrome for the New York Times website About.com, then worked for eight years as the Chronic Pain Health Guide for The HealthCentral Network before coming to ProHealth. To learn more about Karen, see “Meet Karen Lee Richards .”
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