Gut Health and Its Effect on Brain Function

By Rakhi Amirah Khurana

Recent advances in science have deepened our understanding of the complex connection between gut health and brain function. While these two systems might appear separate, they are closely linked, especially through the role of inflammation. This article explores how gut health impacts brain health, highlighting key factors like inflammation, insulin resistance, and shares the six fundamental pillars of brain wellness. 

The Role of Inflammation

Inflammation is the body’s natural response to injury or infection, but when it’s chronic, it can harm the brain. A damaged gut can lead to "leaky gut," where toxins enter the bloodstream, triggering inflammation that affects the brain. Research links this ongoing brain inflammation to neurodegenerative conditions like Alzheimer’s and Parkinson’s.

Insulin Resistance and Brain Health Insulin resistance plays a major role in connecting gut health to brain function. Insulin helps control blood sugar, but when the body becomes resistant to it, blood sugar rises and inflammation increases. This has been linked to a higher risk of cognitive decline and neurodegenerative diseases. A healthy gut microbiome can help improve insulin sensitivity, reducing these risks to brain health.

The Six Pillars of Brain Health

·      Physical Activity (PA): Regular exercise enhances cerebral blood flow, stimulates neurogenesis [the process of creating new brain cells (neurons)] and promotes synaptic plasticity (brain's ability to adapt by strengthening or weakening connections between brain cells), all of which contribute to improved cognitive performance and mental resilience.

•  Sleep: Sleep is essential for neuroplasticity and memory consolidation. Disruptions in sleep patterns, particularly those linked to chronic sleep deprivation, can exacerbate neuroinflammation and accelerate cognitive decline.

•  Chronic Medical Conditions: Effective management of chronic conditions such as type 2 diabetes, hypertension, and cardiovascular disease is vital to mitigating harmful effects on cerebral health. These conditions are linked to higher levels of body-wide inflammation and damage caused by free radicals which can impair brain function.

•    Physical Fitness: Weekly physical activity enhances brain-derived neurotrophic factor (BDNF) levels, supports nerve cell function and strengthens cognitive function, especially in aging populations.

How does physical activity differ from physical fitness? Physical activity refers to any movement of the body that uses energy including walking, dancing or gardening. Physical fitness refers to one’s overall health and one’s ability to perform physical tasks. These are measured by factors such as strength, endurance, flexibility, and cardiovascular health.

•  Social Interaction: Engaging in meaningful social relationships within the community reduces the detrimental effects of stress and enhances emotional well-being, serving as a protective factor against age-related cognitive decline. 

•  Diet and Nutrition: A nutrient-dense diet, rich in fiber, antioxidants, and essential fatty acids like omega-3s (fatty fish, flaxseeds and walnuts) helps protect and restore the gut microbiome, which in turn supports brain function. The gut-brain axis plays a pivotal role in regulating systemic inflammation and neurotransmitter synthesis, making dietary choices extremely fundamental for long-term cognitive health

For those interested in a more in-depth exploration of the topics discussed, I have provided the following video links for further learning.

The first video, Wellness Wednesday: Nutrition and Microbiome (January 6, 2021), delves into the crucial connection between nutrition and gut health. You can watch it here.

Additionally, the second video, Gut Microbiome and Non-Gut Diseases, offers insights into how the microbiome affects not just digestion but a variety of other health conditions. You can view this video here. These resources will provide you with a deeper understanding of the gut microbiome’s impact on overall health.

References

Al Bander, Z., Nitert, M. D., Mousa, A., & Naderpoor, N. (2020). The Gut Microbiota and Inflammation: An Overview. International journal of environmental research and public health, 17(20), 7618. https://doi.org/10.3390/ijerph17207618

Aziz, T., Hussain, N., Hameed, Z., & Lin, L. (2024). Elucidating the role of diet in maintaining gut health to reduce the risk of obesity, cardiovascular and other age-related inflammatory diseases: recent challenges and future recommendations. Gut microbes, 16(1), 2297864. https://doi.org/10.1080/19490976.2023.2297864

British Columbia Children's Hospital. (n.d.). *Gut microbiome and non-gut diseases* [Video]. Retrieved [December 19], from https://www.bcchr.ca/video/gut-microbiome-non-gut-diseases

Jaqua, E., Biddy, E., Moore, C., & Browne, G. (2023). The Impact of the Six Pillars of Lifestyle Medicine on Brain Health. Cureus, 15(2), e34605. https://doi.org/10.7759/cureus.34605

Willette, A. A., Xu, G., Johnson, S. C., Birdsill, A. C., Jonaitis, E. M., Sager, M. A., Hermann, B. P., La Rue, A., Asthana, S., & Bendlin, B. B. (2013). Insulin resistance, brain atrophy, and cognitive performance in late middle-aged adults. Diabetes care, 36(2), 443–449. https://doi.org/10.2337/dc12-0922