Human diseases are affected by both genetic factors and environmental factors.
Genetic factors, as we all know, are hidden in the genome. It can be known by sequencing the genome.
When it comes to environmental factors, it is complicated, including age, diet, lifestyle (such as smoking, staying up late, etc.), living environment (such as rural or urban), and even the usual medications. How to measure all this?
There is a direct and easy way, and that is to look at your gut microbiota. The influence of any environmental factor can eventually be reflected in the gut microbiota. For example, smokers and non-smokers, people living in rural areas and people living in cities, have different composition of gut microbiota. These microorganisms include bacteria, viruses, and fungi that are parasitic in the intestinal tract. The so-called "different composition" refers to the different types of intestinal microorganisms, the proportion of a certain type, etc.
Don’t underestimate the information given to us by intestinal microbes. Recently, a foreign research team investigated 20 diseases that are affected by both genetic and environmental factors, including schizophrenia, Parkinson’s disease, hypertension, asthma, diabetes, and obesity. They found that changes in the intestinal microbiota can better reflect whether a person is likely to suffer from a certain disease than genes. Only type 1 diabetes is an exception.
Why is this so? One possible reason is that the genome is "dead". For example, it is detected that you have an obesity gene, but when and under what circumstances this gene will work, genetic testing cannot tell you. The microbiome is "alive", it can capture changes in all aspects of your life anytime, anywhere. Also, in some cases, the altered gut microbiota can directly cause disease. For example, it has been found that at least three types of intestinal bacteria can cause colon cancer.
Therefore, in the future, we only need to monitor the intestinal ecosystem to help diagnose or even prevent certain diseases. The monitoring method is also quite simple, which is to sequence the microorganisms in the stool sample. In foreign countries, many biological companies have begun to provide such services.