Early life conditions shape the gut microbiome, which can be linked to type 2 diabetes. Dietary changes can be reshaped to prevent and manage this condition.
The Gut Microbiome Influence on Health
The gut microbiome is an ecosystem of microorganisms in our digestive system and strongly influences human health. This diverse community of microbes influences digestion, metabolic processes, immune function, and even mental health. Current research continues to shed light on associations between the gut microbiome and various health conditions like metabolic disorders, including obesity, non-alcoholic liver disease, and type 2 diabetes. Some countries like Singapore recognise this importance by establishing dedicated centres to study the impact of gut health on various diseases.
The initial composition of this gut microbiome is established in the first three years of early life and has a lasting impact on development and health throughout life. Factors like delivery method, antibiotic exposure, and early life stressors can all significantly influence this initial microbial community.
However, research shows that dietary interventions can significantly modulate the gut microbiome, even after this initial programming period. In this article, we delve into the latest research on the association between the gut microbiome and type 2 diabetes. We also look at how specific dietary changes can reshape the gut microbiome to contribute to preventing and managing prediabetes and type 2 diabetes.
The Gut Microbiome’s Link to Type 2 Diabetes
Dysbiosis is a disruption in the balance of gut microbial communities and has been linked to the development of insulin resistance in type 2 diabetes. In prediabetic and type 2 diabetic patients, studies have shown that their gut microbiomes are depleted in bacterial butyrate producers alongside a rise in species that promote inflammation. In addition, dysbiosis also interferes with cellular pathways such as sugar-related membrane transport, resulting in increased cellular glucose uptake and branched-chain amino acid outward transport, which induces insulin resistance. Interestingly, studies have shown that the gut microbiome partly mediates the anti-hyperglycaemic effects of the diabetes drug metformin. Additionally, metformin has a negligible impact on the metabolic imbalance in antibiotic-treated mice. This interaction emphasises the significance of the gut microbiome in drug efficacy, indicating the importance of regulating gut health in patients.
Early Life Programming of the Microbiome
Early life conditions play a pivotal role in shaping the gut microbiome. These can influence susceptibility to diseases later in life. Treatment with antibiotics during pregnancy can lead to a dominance of Enterococcus faecalis in infants, which can impact the development of the infant’s immune system. Caesarean section has been linked with a higher risk of the child developing type 1 diabetes. Maternal diet during pregnancy can affect the foetus’ gut microbiota, where a high-fat diet is associated with an imbalance in Akkermansia and Bifidobacterium species, which have been linked to obesity and type 2 diabetes.
Other interesting aspects of early life environments that can also affect the microbiome are maternal mental health and the presence of early life stressors like famine. In a recent study from China, individuals exposed to famine during the first 1000 days of life (born in 1959) exhibited lower gut microbial alpha diversity during adulthood and increased risk of type 2 diabetes. Understanding these interactions is crucial for healthcare professionals as they guide patients in using diet to manage blood glucose levels and improve overall health.
Practical Dietary Recommendations for Gut Microbiome Health
Even after considering the influence of early life on the gut microbiome, dietary interventions remain a powerful tool for enhancing health and mitigating disease risk. Healthcare professionals can offer practical advice to guide prediabetic and type 2 diabetic patients to make some of these dietary changes to impact their gut microbiome positively:
Increase Fibre Intake
Consuming a diet high in fibre from fruits, vegetables, nuts, seeds, legumes, and whole grains. Consequently, this can promote the growth of beneficial gut bacteria. These foods can enhance the production of short-chain fatty acids, improving insulin sensitivity and reducing inflammation. They also produce 3-indole-propionic acid, which helps improve blood glucose utilisation.
Reduce Food High in Animal Fats and Proteins
Diets rich in animal fats and proteins can further disrupt the balance of the gut microbiome. The imbalance will lead to increased protein breakdown, producing substances like branched-chain fatty acids, gases, and other compounds that can make the gut more acidic. This increases lipopolysaccharides in the blood, causing low-level inflammation linked to insulin resistance.
Incorporate Fermented Foods
Including fermented foods such as yoghurt, kefir, and sauerkraut in the diet can introduce beneficial probiotics to the gut. Additionally, these probiotics can help modulate the immune system and improve the gut barrier function. This could potentially lead to better glucose control.
Limit Sugar and Processed Foods
Reducing the intake of sugar and processed foods can decrease the abundance of harmful bacteria that thrive on simple sugars. This change can help reduce gut inflammation and improve insulin signalling pathways.
Plant-Based Diet
Adopting a plant-based diet can diversify the gut microbiome. Subsequently, a varied microbiome can enhance insulin sensitivity by influencing the gut-brain axis and regulating hormones that control appetite and metabolism.
Include Omega-3 Fatty Acids
Foods rich in omega-3 fatty acids, like fish, can have anti-inflammatory effects on the gut microbiome. Omega-3s also increase the diversity of the gut microbiome and can modulate the expression of genes involved in insulin signalling and glucose metabolism, thereby improving insulin resistance.
Other than dietary changes, physical activity, stress, sleep, and smoking can affect blood sugar levels. Regular exercise, stress management techniques like meditation or yoga, adequate sleep, and quitting smoking all contribute to controlling blood sugar levels and lowering the risk of diabetes complications. Combining these dietary and lifestyle recommendations provides a comprehensive approach to managing blood sugar levels and supporting overall health.
Harmonising Health: The Microbiome’s Role in Lifelong Health
The gut microbiome is a lifelong companion, pivotal to our health from infancy through adulthood. Birth conditions and diet influence its early formation, yet remain malleable and responsive to dietary choices such as increased fibre, reduced animal fats, and the inclusion of fermented foods. Beyond nutrition, lifestyle factors like exercise and stress management play a crucial role. Together, on top of medication, healthcare professionals can offer a holistic strategy for managing blood sugar and enhancing well-being, emphasising the importance of gut health and the microbiome’s dynamic role in patients’ health.
References
- Takeuchi, T., Kubota, T., Nakanishi, Y., et al. (2023). Gut microbial carbohydrate metabolism contributes to insulin resistance. Nature, 621, 389–395. https://doi.org/10.1038/s41586-023-06466-x
- Li, S. X., & Guo, Y. (2023). Gut microbiome: New perspectives for type 2 diabetes prevention and treatment. World Journal of Clinical Cases, 11(31), 7508–7520. https://doi.org/10.12998/wjcc.v11.i31.7508
- Fan, Y., & Pedersen, O. (2021). Gut microbiota in human metabolic health and disease. Nature Reviews Microbiology, 19, 55–71. https://doi.org/10.1038/s41579-020-0433-9
- Sarkar, A., Yoo, J. Y., Dutra, V. O., Morgan, K. H., & Groer, M. (2021). The Association between Early-Life Gut Microbiota and Long-Term Health and Diseases. Journal of Clinical Medicine, 10(3), 459. https://doi.org/10.3390/jcm10030459
- Gou, W., Wang, H., Tang, X. Y., et al. (2023). Early-life exposure to the Great Chinese Famine and gut microbiome disruption across adulthood for type 2 diabetes: three population-based cohort studies. BMC Medicine, 21, 414. https://doi.org/10.1186/s12916-023-03123-y
- Menni, C., Zierer, J., Pallister, T., et al. (2017). Omega-3 fatty acids correlate with gut microbiome diversity and production of N-carbamylglutamate in middle-aged and elderly women. Scientific Reports, 7, 11079. https://doi.org/10.1038/s41598-017-10382-2
