Dysbiosis (also called dysbacteriosis) is a term for a microbial imbalance or maladaptation on or inside the body, such as an impaired microbiota. For example, a part of the human microbiota, such as the skin flora, gut flora, or vaginal flora, can become deranged, with normally dominating species underrepresented and normally outcompeted or contained species increasing to fill the void. Dysbiosis is most commonly reported as a condition in the gastrointestinal tract, particularly during small intestinal bacterial overgrowth (SIBO) or small intestinal fungal overgrowth (SIFO). It has been reported to be associated with illnesses, such as periodontal disease, inflammatory bowel disease,chronic fatigue syndrome,obesity,cancer,bacterial vaginosis, and colitis.
Typical microbial colonies found on or in the body are normally benign or beneficial. These beneficial and appropriately sized microbial colonies carry out a series of helpful and necessary functions, such as aiding in digestion. They also help protect the body from the penetration of pathogenic microbes. These beneficial microbial colonies compete with each other for space and resources and outnumber human cells by a factor 10:1.
Dysbiosis may be caused by such diverse things as repeated and inappropriate antibiotic exposure,alcohol misuse, or inappropriate diet.
When this balance is disturbed, these colonies exhibit a decreased ability to check each other's growth, which can then lead to overgrowth of one or more of the disturbed colonies which may further damage some of the other smaller beneficial ones in a vicious cycle. As more beneficial colonies are damaged, making the imbalance more pronounced, more overgrowth issues occur because the damaged colonies are less able to check the growth of the overgrowing ones. If this goes unchecked long enough, a pervasive and chronic imbalance between colonies will set in, which ultimately minimizes the beneficial nature of these colonies as a whole.