Monitoring changes in bacteria in the gut could provide an early warning of Type 2 diabetes, a study has found.
The early alarm could be used to target those who would most benefit from lifestyle change and preventive approaches, the study authors said.
Analysis of data from hundreds of thousands of people identified changes in the composition of the gut microbiome – the community of microorganisms that lives in the gastrointestinal tract – that can be detected before the onset of any changes in blood glucose measures.
Previous studies have found strong links between diabetes and gut microbiome but failed to consistently agree on the key bacteria across large populations.
Current tests look for higher levels of sugar in the blood, but do not flag people with normal levels who may be at risk in the future. Risk is assessed by looking at factors such as age, sex, weight and family history.
The findings represent a “major step forward in understanding how our gut microbiome is linked directly with metabolic disease”, said Prof Tim Spector, scientific co-founder of health data firm Zoe and one of the study’s authors. “Identifying these clear microbial changes before blood sugar levels worsen could lead to earlier intervention with food and lifestyle choices, as well as treatment options, to prevent Type 2 diabetes.”
The study, presented at the annual meeting of the European Association for the Study of Diabetes in Milan, involved nearly 230,000 adults in the UK and US.
The team identified 789 species of bacteria linked to diabetes present in those with the condition or prediabetes.
They then tested the blood sugar of people with normal glycaemic levels two hours after eating a meal. Levels temporarily rise after eating, but if it remains high it can be a sign that muscles are not responding well to insulin, an early step on the path to Type 2 diabetes.
They found those whose blood sugar remained high also were more likely to have the pattern of bacteria seen in those with diabetes.
“We know that lifestyle changes, like diet and physical activity, can prevent or delay the onset of T2D,” said Dr Gabriel Baldanzi, of the Laboratory of Computational Metagenomics at the University of Trento in Italy.
“But people often struggle to notice these changes are working, beyond perhaps losing some weight. If we can detect early shifts in the gut microbiome and show someone they are on the right track, that could be a powerful source of motivation to keep going.”
