Gut microbiome can provide information about the health of the body

The sample consisted of 893 people who underwent routine annual medical examinations at a tertiary medical center. Data were collected from electronic medical records, laboratory tests, ICD‑10 codes, prescribed medications, a treadmill stress test (Bruce protocol), and detailed questionnaires about diet and lifestyle. The composition of the microbiome was determined by sequencing the 16S gene (V4).

It turned out that the index is highly dependent on daily habits, both in people without diagnosed diseases and in those who already have hypertension or metabolic syndrome. High fiber intake, adherence to the Mediterranean diet, and better physical fitness correlated with a healthier microbiome and an improved lipid profile. Ultra‑processed food and elevated levels of subclinical inflammation, by contrast, reduced MHI.

Physical activity was assessed objectively — through MET (metabolic equivalents) based on the results of a stress test. The positive correlation between MET and MHI suggests that physical activity affects not only the cardiovascular system but also the structure of the microbiome, which supports systemic health.

Researchers used regression models to estimate the behavioral “dose” required to change an individual’s MHI by 0.5 points — a shift that, as previously shown, is associated with a noticeable increase in microbial resistance and is linked to a variety of diseases. Based on published intervention studies, the authors demonstrated that the index responds quickly to dietary changes and shifts within the predicted range.

An important conclusion is that the same bacteria can be involved in both pathogenic and lifestyle‑related effects. This means that they do not directly cause health problems but respond to the effects and conditions of the host organism. MHI reflects the intersection of lifestyle, environment, and biology, which makes it potentially applicable both in clinical settings and in public health strategies.