Diet, T1D, and the Microbiome 

Diet, T1D, and the Microbiome 

By: Jenna Feeley 


Research continually shows that diet plays an integral role in modulating the microbiome. Because the microbiome has a profound impact on many systems within the body, monitoring and adjusting dietary habits to fit individual patient needs is central to maintaining health and wellbeing. This is even more important for those who are living with or are susceptible to autoimmune conditions, as the microbiome plays an important role in immune regulation. This article will take a closer look at how dietary habits impact the microbiome and subsequently how this impacts those who live with or who are susceptible to developing T1D.

Short Chain Fatty Acids Protect Against T1D

Lactate and butyrate, which are Short Chain Fatty Acids (SCFAs), seem to play a protective effect in T1D development. Decreased levels of lactate and butyrate producing bacteria have been linked to pancreatic beta cell autoimmunity. Bacteria metabolize nondigestible carbohydrates such as those found in fruits and vegetables in order to produce SCFAs. Therefore, it is important that T1D susceptible patients consume a diet high in nondigestible carbohydrates to ensure healthy levels of SCFAs.

Bacteroides & Beta Cell Autoimmunity

The Bacteroides species of bacteria are pathogenic and commonly found in clinical infections.  Increased levels of Bacteroides species can lead to beta cell autoimmunity and a dysbiotic state that may leave patients susceptible to T1D development. Higher levels of Bacteroides have been observed in those who consume high levels of saturated fat and animal protein. Alternatively, the protein casein, a protein found in milk, was found to have a protective impact against beta cell autoimmunity in patients who are susceptible to T1D development. Lastly, a gluten free diet may protect against autoimmune disorder development by increasing the Akkermansia species and decreasing Bifidobacterium, Tannerella, and Barnesiella species.

Ketogenic Diet, the Microbiome, & T1D

Ketogenic diets have been utilized by T1D patients in order to tighten blood glucose control; decreased carbohydrate load helps to reduce insulin needs and blood glucose fluctuations. Ketogenic diets may also modulate the immune system by altering microbiome contents. In mice it was found that decreased levels of Bifidobacteria (from a ketogenic diet) leads to a reduction of Th17 cells which subsequently reduces immune activation. Therefore, decreasing the Bifidobacteria species through a ketogenic diet would be beneficial for T1D patients as it would decrease unnecessary immune activation.

The takeaway: The diet plays an important role in maintaining health; however, with our new understanding of the microbiome and its far-reaching effects on overall health, our diet may be impacting us more than we previously thought. For T1D patients, diet impacts both the immune system (i.e. autoimmune attack against beta cells) in addition to daily blood sugar management. It is therefore imperative that T1D patients find a way of eating that supports their individual needs and promotes overall health. This may also be applied to those who are susceptible to T1D development as balancing the microbiome could potentially protect against autoimmune diseases. 



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