Though a person's microbiome is generally stable throughout his/her lifetime, there are notable differences from person to person. Though associations between the microbiome and gastrointestinal diseases may seem sensible, the implications may actually reach well beyond the gut. A newly published study suggests a link between the bacterial content of the human gut with the development of Alzheimer's Disease (AD). The study found a particular composition of bacteria in the microbiome of AD patients that lacked bacterial diversity was correlated with markers in cerebrospinal fluid from the same patients. Previous studies have drawn this link in animals with gut bacterial content affecting the production of amyloid, the trademark protein in AD. However, this is the first study demonstrating this link in human, and also hinted at other potential diseases including Type 2 Diabetes and Parkinson's Disease as well.

While this is in the early stages of being researched, it will be exciting to see if this leads to the normalization or treatment of gut bacterial health as a way to treat AD and other diseases. With the high use of antibiotics, it also brings into question what effect, if any, the repeated use of antibiotics in an individual and an expecting mother may have in the development of AD.