A team of researchers in Sweden has developed a mathematical model, based on the composition of microbes in their gut, to help explain why people react in different ways to a particular diet.
The 300 to 1,000 different types of microorganisms found inside the human digestive system are collectively referred to as gut microbiome and while they remain typically stable in individuals their composition can differ widely based on genetic factors, transference from the mother at birth, diet and long-term drug use among others.
Microbiome have also been found to play an important role in the metabolism of food and an increasing number of studies have associated the microbiome with human disorders. However, the new research goes beyond mere association studies and attempts to elucidate causalities arising from the microbes’ interaction with food.
Through clinical trials, the research team has been able to establish one such causal link. In the trials, the researchers diagnosed the gut microbiome of 45 overweight people who were then divided into two groups — one group with a diverse gut microbiome and another with a low-diversity gut microbiome
The participants then followed a low-calorie diet for six weeks. During this time, the researchers assessed the participants' blood and feces for the content of substances known to be markers of disease and ill health.
While all of the participants lost weight as expected, the researchers found that the participants in the low-diverse group also had reduced content of the substances known to indicate ill health. In comparison, the participants with a diverse gut microbiome did not have a reduction in such content.
Explaining their findings, the researchers said that among other things the intestines of individuals with low-diversity gut microbiome produce fewer amino acids when they follow this diet, which could explain the improved blood chemistry.
According to researchers, these findings will help physicians identify overweight patients at an increased risk of cardio-metabolic disease who would derive significant benefit from making alterations to their diet.
The team believes that soon clinicians will be able to make dietary recommendations tailored specifically to a patient's gut microbiome and that in the long-term they might be able to add intestinal bacteria for patients whose metabolism does not function properly.