The influence of the gut flora on the thyroid
As we wrote in the previous blog post, there are many factors that affect how the thyroid functions. These include the seasons, diet, or medication use. Thanks to new insights, one more factor has been added: the gut flora.
Gut flora and hormones
The billions of microorganisms that live in your intestines have a major influence on the production of hormones, including thyroid hormones. This is no surprise in light of the growing understanding that the gut flora seems to be connected to virtually all vital bodily functions.
Conversion of T4 to T3
Gut microbes can recognize various hormonal substances such as the adrenal hormones adrenaline and noradrenaline, as well as thyroid hormones. They can even regulate and influence hormones. In the case of thyroid hormones, the microorganisms in the gut assist in the conversion of T4 to T3. About 20 percent of total T4 is converted to T3 in the intestines.
The digestive system influences the thyroid
Bile salts that enter the small intestine after eating fats also have an influence on the thyroid, through the increase of an enzyme that converts T4 to T3 (iodothyronine deiodinase). The digestive system is therefore not something that can be ignored as a factor in thyroid function.
The “blind spot” in Western science
Experts in the emerging field of “systems biology” therefore call for better integration of the gut flora in bringing about medical progress. This is a blind spot in modern Western science.
Only 1% human
Because we have about 20,000 human genes and about 2 to 20 million microbial genes, “we” are only 1% human. Let that sink in: of all the genes we carry with us, only one hundredth is Homo sapiens. All the other genes come from microorganisms such as bacteria on the skin or in the intestinal tract. Ignoring this 99% of our internal and external “gene pool” is therefore actually very illogical.
Complex problems
The growing knowledge of this complicated ecosystem in the gut does not make things any easier. To properly understand the complex whole, ordinary biology is no longer really sufficient. System problems are therefore increasingly central in both biology and medicine.
Systems biology
Systems biology is the study of systems of biological components such as molecules, cells, organisms, or entire species. Living systems are dynamic and complex, and their behavior is difficult to predict based on their individual parts. By understanding the whole (using, among other things, bioinformatics, biology, computer science, engineering, and physics), new knowledge emerges that also makes it possible to predict how systems change over time. The whole is greater than the sum of its parts.
Gut flora as a solution
Sometimes it even seems more logical to look for solutions not in human genes, but in the composition of the gut flora. Of course, that is easier said than done, because it requires a paradigm shift in the thinking of the many sciences concerned with nutrition, biology, and medicine.
Multiple factors
For the thyroid, it is important to know that its functioning is determined not by one system, but by many systems together. These are located in seemingly separate regions of the body, but functionally they are closely connected.
