A new study has identified links between alterations in gut microbial populations and multiple markers of obesity and type 2 diabetes.

Changes to the gut microbiome and its associated genes are increasingly thought to be involved in obesity and type 2 diabetes through complex mechanisms that are not fully elucidated.

Until now, scientists have focused on understanding the role of one gut microbial shift on one marker. This new research suggests that microbiome changes may in fact exert a more or less incidental influence on almost everything.

Researchers have found over 27 metabolic markers, including body fat, HbA1c, insulin resistance (HOMA-IR), appetite regulation and inflammatory factors, that correlate with microbiome changes, suggesting that such a ripple effect exists.

The team of scientists from Shanghai Jiao Tong University School of Medicine analysed gut DNA sequencing data in different populations: lean versus obese young Chinese as well as in adult Chinese who underwent bariatric surgery.

They isolated groups of genes pertaining to specific microbe species with the aim to determine how much of a genetic control of obesity originated from the gut microbiome.

The findings, which appeared in the journal Nature Medicine, show that there is about 200 of those microbial gene clusters that could impact more than 100 of known core genes playing a role in obesity.

Researchers discovered what function serves certain of those identified gut microbial genes and, unsurprisingly, some have been found to play a role in fat accumulation while others appear to regulate inflammation.

They have also linked certain gut microbe species in obese participants to things like defective glucose disposal pathways, pro-inflammatory molecules, as well as metabolites that are known risk factors for type 2 diabetes and cardiovascular disease.

What all of this suggests is that there may be a causal relationship between changes in the gut microbiomen, its associated genes and metabolic features mentioned earlier.

Such features or traits could be the work of thousands of gene variations in the gut microbiomen, working in concert. The vast majority of them have only tiny effects, but together they could be powerful.

Now researchers have to understand how combinations of seemingly hundreds or thousands of gut microbial genes work together in very complicated ways and how they lead to metabolic disorders.