Probiotics are live, good bacteria that are beneficial for your health, especially your digestive system. The average human body is teeming with bacteria, and while this may be hard to believe, these microbes are essential in maintaining good health. There are trillions of bacteria living in your gut, or digestive tract, and more than 400 different species have been identified! While most of the microbes are beneficial to us, an imbalance between the good and bad bacteria may cause various illnesses or ailments. Probiotics are considered “good” bacteria because they help keep your gut healthy. (continued)
Main Types of Probiotics
Current health studies have shown that beneficial strains have reaped much health benefits from the following genera:
Lactobacillus, Bifidobacterium, Saccharomyces, Streptococcus, Escherichia coli and Bacillus. (continued)
Lactic acid bacteria work by converting sugars to lactic acid, thereby producing a harsh environment in which harmful bacteria growth is inhibited. Lactobacilli can be found in its natural state in the vagina and gastrointestinal tract. Its therapeutic effects are well researched and documented. However, most Lactobacilli are not able to form and colonize in substantial numbers in the intestinal tract.  In fact, it has been noted that a short term, daily dosage of live, probiotic Lactobacilli was not sufficient in creating substantial colony forming units. 
The use of Soil-Based Probiotics has recently gained great interest in the probiotics arena due to the many positive qualities associated with spore-forming bacteria. Its main characteristic includes the formation of an endospore which results in it being resistant to heat (thereby allowing for a long shelf life at room temperature); survivability through the highly acidic stomach environment; and ultimately resulting in a large number of viable microbes to reach the lower intestine.  (continued)
What are Colony Forming Units (CFUs)?
CFU stands for “colony forming units” and is used to measure the number of bacteria in a probiotic formula that are capable of dividing and forming colonies. Each colony is assumed to have derived from a viable, single CFU of a bacteria, yeast or mold. Cells utilize the nutrients in a medium to form and to create colonies. Other factors that are conducive for these cells to metabolize are temperature and oxygen availability.
Where probiotics are concerned, only the viable organisms in a sample that are capable of reproducing, or colonizing, are considered.
What about Spores?
Spore formers are unique in that their life cycle involves spore germination, proliferation and once nutrients are exhausted, spore germination once again! The ability to have a dual life cycle of growth especially in the harsh, acidic environment of the stomach, is what separates soil-based probiotics from others and establishes their efficacy as a probiotic. 
The microbiome is defined as all the microbes that live in or on the human body. The human body contains nearly 100 trillion cells, but what’s even more astounding is that most of those cells come from bacteria, viruses and other microorganisms. Only one out of 10 cells is actually human; the rest are microbes! What’s more, the microbiome also includes all the metabolic functions of supporting human health. These microbes colonize in our bodies and affect our digestion, immune system, gastrointestinal function, vitamin absorption, protection against disease-causing bacteria, and other vital roles in human health. While most of the microbes are beneficial to us, an imbalance between the good and bad bacteria, or dysbiosis, may wreak havoc in the form of illnesses or ailments.
“All disease begins in the gut.” — Hippocrates
Our digestive system is also called the “enteric nervous system” or our second brain. Containing as many neurons as does the spinal cord, the gut truly does have a mind of its own. The vagus nerve, which is the longest nerve in the human body, connects the gastrointestinal tract and the brain. This nerve conveys your “gut feelings” from your stomach to the brain, affecting your hunger pangs, satiety, mood and stress levels. The brain can also send signals to the gut, where even mild stress can affect the microbial balance in the gut, affecting your digestion, production of digestive enzymes and gastrointestinal function.
When there’s a microbial imbalance in the gut, your immune system is directly impacted. The immune system is not only made up of white blood cells or lymph glands; most of its functions take place in the human gut. Containing more immune cells than the rest of our body, the human gut, then, plays a substantial role in our immune function.  Our digestive system is designed to remove bacteria, viruses and toxins from our food before it can permeate through the rest of our body.
The beneficial microbes in the gut and the immune system work efficiently together in a healthy person. However, microbial balance is often disrupted due to poor nutrition, medication, overuse of antibiotics, stress, environmental toxins and other factors. The immune system’s response to defend the body against this imbalance is inflammation. If the immune cells continue to attack healthy cells after the healing process, then the mind and body “ping-pong” distress signals to each other, and serious health conditions may occur. Research has shown that inflammation is linked to mood disorders such as anxiety and depression. Probiotics may reduce the inflammation that is connected to such mental disorders.
Lab tests for Inflammation * C-reactive protein test is a blood test that can high levels of C-reactive protein. This protein produced by the liver when there is inflammation, infection and injury. * Food allergy testing may reveal the body’s immune response to inflammation.
* A cytokine test may reveal the presence of cytokines as an indicator of inflammation. Cytokines are proteins that communicate act between immune cells to trigger an inflammatory response.
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