It seems that as our microbiota develops as we get older, the variety of gut bacteria we have could impact our risk of developing type 1 or type 2 diabetes. How do we know this?

Some of what we know comes from researchers who have studied children from countries, such as Finland, Germany, Italy, Mexico, Turkey, and the U.S, to find a link between the intestinal microbiota and type 1 diabetes. Common findings were those with type 1 diabetes had:

• More bacteria from the Bacteroides species
• Fewer bacteria that produce short-chain fatty acids

There is also evidence to suggest that some bacteria, namely those producing lactate and butyrate, are beneficial to maintaining a healthy gut. When these bacteria are altered and/or fall out of balance, it is thought there could be a reduction in the creation of mucins, a type of protein that lubricates and protects the lining of the gut. This has been noted to contribute to the development of type 2 diabetes; however, the research is still new, and the findings need to be confirmed in large population studies.

Around 90% of bacteria in the gut comes from the group Bacteroidetes (Gram-negative) and Firmicutes (Gram-positive).

Several studies have looked at the relationship between gut microbiota and type 2 diabetes. Diabetics were found to have significantly less Firmicutes bacteria in one study compared to non-lean diabetics. Another study in China found participants with T2DM had a reduced level of specific types of Firmicute bacteria.

It has been reported that a reduction in the diversity of the gut bacteria can breach the cell-to-cell integrity, which risks causing leaky gut. This can cause inflammation and an altered immune response, which can impact disorders such as type 1 diabetes.