What is Diabetes?

Diabetes is a disease that occurs when the pancreas is unable to produce enough insulin, or the body is unable to efficiently utilize the insulin it produces. Insulin is a hormone produced by specialized pancreatic cells called β-cells. It is responsible for maintaining glucose levels (blood sugar) in the body. Type 2 diabetes is a type of diabetes where the pancreas produces enough insulin but cells in the organs and tissues (such as the liver and muscle) are unable to effectively utilize this hormone to maintain blood sugar levels. This inability of the muscles, fatty tissues, and liver, to use insulin for the uptake of glucose in the blood is referred to as insulin resistance. According to the World Health Organization, diabetes was the direct cause of 1.6 million deaths in 2021. Another 460,000 kidney disease deaths were caused by diabetes and around 20% of cardiovascular deaths are attributed to increased blood glucose.

What Causes Diabetes?

Type 2 diabetes can be caused by genetic and environmental factors, with genetic factors being accelerated by certain trigger molecules such as sugar and excess fat consumption. One such report on obese populations in Europe and the USA suggested that sugar-sweetened beverage intake was associated with an increased risk of Type 2 diabetes. Other risk factors such as obesity, a sedentary lifestyle, and an aging population, have also been associated with the onset of the disease. Interestingly, gut microbial dysbiosis — a lack of microbial diversity and the loss of beneficial bacteria in the gut (such as those belonging to the Bacteroides family) have been reported in several studies as a factor in the rapid progression of insulin resistance and Type 2 diabetes.

Diabetes and Gut Health Link

The gut microbiota plays a vital role in the modulation of several biochemical activities. Following the consumption of food composed of complex sugars (polysaccharides), the gut microbiota induces the fermentation of such sugars to produce short-chain fatty acids (SCFAs) that nourish the epithelial cells in the colon and strengthen intestinal barrier function. SCFAs that the gut microbiota produce is absorbed into the bloodstream and can reach distant tissues such as the liver, adipose tissue, and kidneys through cell signaling. Studies have found that during the process of signaling, SCFAs increase insulin sensitivity (that is, the responsiveness of cells to insulin, thereby lowering blood sugar levels), suppress the accumulation of fat in adipose tissue, and promote the metabolism of glucose in places such as the liver. One such SCFA that has been well-studied to have this effect is butyrate. As a result, modulating the activity of SCFAs by the gut can be crucial to regulating blood glucose levels, thereby preventing the onset of Type 2 diabetes.

Gut Bacteria and Type 2 Diabetes

Another factor that could play a role in the development of Type 2 diabetes comes from the composition of some bacteria itself. Lipopolysaccharide (LPS) is a “coat” that can be found on the surface of some species of bacteria — both beneficial and pathogenic. However, on their own, LPS molecules are toxins that are known to initiate inflammatory processes associated with obesity and insulin resistance. With the consumption of high-fat diet foods, there is an enrichment of the Gram-negative class of bacteria. Gram-negative bacteria are known to produce high amounts of LPS. The subsequent over-abundance of LPS in the gut can cause a leaky gut, thereby allowing the escape of LPS into the blood circulatory system. Once in the blood, LPS infiltrates tissues such as those in the liver and fatty tissues, triggering an innate immune response and altering the activity of the cells present in those tissues. This can lead to impaired glucose metabolism in the liver, and insulin insensitivity, potentially leading to metabolic diseases like Type 2 disease. This is important because studies have shown increased levels of toxins like LPS in patients with Type 2 diabetes and obesity.

Excessive intake of food rich in carbohydrates and fat can alter the microbiome composition in our gut. Once this alteration occurs, it can be toxins finding their way out of the gut into the blood which can reduce the activity of organs like the liver to uptake insulin or low-grade inflammation that also results in insulin resistance, a feature that characterizes Type 2 diabetes.

Gut Microbiome and Diabetes

The gut microbiome plays a significant role in regulating glucose metabolism and reducing inflammation, which are crucial in managing Type 2 diabetes. Research shows that individuals with Type 2 diabetes often have a less diverse microbiome, with a higher prevalence of harmful bacteria that can contribute to insulin resistance. On the other hand, beneficial bacteria that produce short-chain fatty acids (SCFAs), like butyrate, support improved insulin sensitivity and metabolic health. A balanced gut microbiome can therefore help in lowering blood sugar levels and preventing complications associated with diabetes.

Steps to Improve Gut Health and Reduce Diabetes Risk

• Eat More Fiber-Rich Foods: Incorporating fiber-rich foods like whole grains, fruits, vegetables, and legumes helps feed beneficial gut bacteria. Dietary fiber is a key fuel source for these microbes, enabling them to produce short-chain fatty acids (SCFAs), such as butyrate, which enhance insulin sensitivity, reduce inflammation, and improve overall gut barrier function. Aim for a variety of fiber sources to promote a diverse microbiome.
• Incorporate Fermented Foods: Fermented foods like yogurt, kefir, kimchi, sauerkraut, and miso are rich in probiotics—live bacteria that can replenish and balance the gut microbiota. These foods not only introduce beneficial bacteria but also improve the diversity of the microbiome, which is essential for optimal gut health and glucose metabolism. Choosing products with live and active cultures ensures maximum benefits.
• Limit Processed and Sugary Foods: Processed foods high in sugar, unhealthy fats, and additives disrupt the balance of the gut microbiome, promoting the growth of harmful bacteria. This can lead to gut inflammation, insulin resistance, and metabolic issues. Reducing the intake of sugary snacks, soft drinks, and fried foods helps maintain a healthier gut environment and supports overall metabolic health.
• Engage in Regular Physical Activity: Exercise not only improves cardiovascular and metabolic health but also positively impacts gut microbiome diversity. Activities such as walking, jogging, cycling, or yoga can promote the growth of beneficial bacteria and enhance insulin sensitivity. Aim for at least 150 minutes of moderate-intensity exercise per week to reap these benefits.
• Practice Stress Management Techniques: Chronic stress can negatively affect the gut by altering its microbial composition and reducing its protective functions. Practices like meditation, deep breathing, yoga, or mindfulness help regulate stress hormones, which in turn support a healthier gut microbiome. Prioritizing self-care and relaxation can have lasting positive effects on gut health and blood sugar control.

By adopting these steps, individuals can support a robust gut microbiome, which plays a crucial role in managing blood sugar levels and reducing the risk of Type 2 diabetes.