There are some very exciting discoveries about dramatic interactions between the organisms living in the intestines of humans and how they influence not only nutrition (weight and growth) and our immune system but human behavior. They may also have influence on sexuality.
Researchers have been making very intriguing discoveries in the last century or so. As we know the germ theory is relatively new knowledge and we think of germs as bad. We understand that the first “living” thing was a single cell. For over 2 billion years the only living things on this planet consisted of single cells. These cells converted carbon, nitrogen, sulfur and phosphorus into compounds that can be used by plants and animals. They use the energy of the sun (photosynthesis) to ma ke their own food and one of their waste products is oxygen.
Gradually over those billions of years they evolved into plant and animal forms. Humans evolved into huge communities of bacteria and other microbes. It is impossible to count how many microbes that the average person contains but maybe about ten microbial cells to every human one. By any count the human body contains trillions. For more details about microbes the book I Contain Multitudes by Ed Yong is full of information.
Also from his book is a discussion about a bacteria, Wolbachia, which was found in a group of asexual, all female wasps. They reproduced by cloning themselves. When the wasps were treated with antibiotics the males suddenly reappeared and both sexes started mating again. Wolbachia is a very successful bacteria infecting about 4 out of ten arthropods. It can help some and harm others. They don’t all become asexual. Wolbachia are neither good nor bad. It depends on how the host and the bacteria relate to each other at any given time or place. It also depends on the complex genetic makeup of the host and how it interacts with the microbe.
Early in this century Patterson and Mazmanian began working with mice on associations of the activation of the maternal immune system and autistic behaviors. Certain microbes caused a maternal immune response that made their offspring have a permeable gut and an unusual collection of microbes. These microbes produce chemicals into the blood stream that triggered abnormal atypical behaviors in the offspring. These mouse studies have led to numerous studies of the interactions of the gut microbiomes and autistic behaviors.
Follow up studies have been looking at the association between gut microbiomes and autistic behaviors. Dr. Qi Su from Hong Kong identified specific archaea, bacteria, fungi, viruses, microbial genes and metabolic pathways that were found in children diagnosed with autism. They then examined the gut microbiome of 1,627 children with and without autism and were able to identify over 80% of the children diagnosed with autism.
While there is still no simple medical test to identify the causes of autistic behaviors the relationship to gut microbiomes is present. There is a clear mind-body connection but the complexity is “mind-boggling”.
by Sally Robinson, MD Clinical Professor
Keeping Kids Healthy
Published July 2024