Researchers have identified specific types of microorganisms that directly influence body weight and metabolism in humans. By analyzing data from tens of thousands of people, they developed an accurate system for assessing the state of the human microbiome.

The Impact of Gut Bacteria on Health

In recent years, gut microflora has received special attention due to its close connection with overall well-being. Medical professionals already know that the composition of the gut microbiome affects the risk of developing type 2 diabetes and cardiovascular diseases. However, science is only beginning to unravel this complex world, and many mechanisms of its functioning remain unclear.

Challenges in Finding Universal Markers

Until recently, it was difficult to identify universal indicators of a healthy gut because of significant individual differences among people. Diet influences the composition of the microbiome, and each person's response is unique. There was also a lack of large-scale studies involving thousands of participants that considered both their diets and medical indicators. The new research has filled this gap, allowing scientists to link specific types of microbes to particular diagnoses.

Large-Scale Study and Data Analysis

A team of biologists analyzed data from over 34,000 people in the USA and the UK. In the study, published in the journal Nature, researchers collected microbiome samples, detailed dietary information, as well as blood test results and blood pressure measurements from participants. All data were sourced from the large ZOE PREDICT program.

Using machine learning methods, the team studied 661 types of microbes. The algorithm searched for correlations between the presence of these bacteria and risk factors such as body mass index, blood sugar, and cholesterol levels. Each microorganism was assigned a score: bacteria associated with good health received values closer to zero, while those linked to health problems were closer to one.

Beneficial and Harmful Bacterial Species

As a result, specialists identified the 50 most beneficial and 50 most harmful species. Beneficial microorganisms were more common in people who consumed a lot of plant-based foods and were associated with lower blood fat levels and normal blood pressure. Harmful species predominated among participants with obesity and cardiovascular disorders.

Interestingly, people of normal weight had, on average, five more beneficial bacterial species than those with obesity. Many of the "good" microbes were previously unknown to science and did not even have names, while the "bad" bacteria are already well-studied and have long been linked to inflammatory processes.

The Influence of Diet on the Microbiome

The study confirmed that the composition of the microbiome can be altered through diet. In additional experiments, participants changed their eating habits or took prebiotics, which led to an increase in the number of beneficial bacteria, such as Bifidobacterium animalis, and a decrease in harmful ones.

A New Tool for Medicine

The developed rating system (ZOE Microbiome Health Ranking 2025) has demonstrated a stable link between diet, the microbiome, and human health. This tool will enable doctors and biologists in the future to more accurately assess patients' conditions and develop personalized diets for disease prevention.