Dr. Amita Joshi, PhD

"Do you want to live long?" OR "Do you want to live a long, healthy life?"

These are two distinctly different questions. No one would like to spend their long-life bed-ridden or with persistent nagging pain. The difference between "long life" and "long and healthy life" is becoming more meaningful, especially in the midst of the COVID-19 pandemic. Focus on having a healthy life has never been more critical than today. Ironically, we all have been searching for that elusive Elixir for a healthy life in the world outside.

Intriguingly, the secret of a healthy and long life resides in our gut, a fact very much known and documented in ancient medicine. Our ancestors likely understood this, while we are just waking up to it today. Historically, Ayurveda described the gut microflora as the sustaining force for life. Much later, Elie Metchnikoff, in 1907, gave the first scientific evidence that Lactobacilli (beneficial bacteria found in our gut), helps maintain health and longevity.

With the increase in average life span, global cases of age-related disorders like Alzheimer's and Parkinson's have also seen a rapid rise. Interestingly, people living in 'blue zones' live a long life and live free from any such age-related condition. Diet and exercise have been found to be critical factors for long and healthy life in the 'blue zone'. This clearly implies the importance of diet and gut for a healthy life.

Understanding the role of Gut in human health

You would be surprised, but our bodies house ten times more microorganisms than human cells. This microbial population is known as microbiota. Our gut is the home for the fascinating ecosystem of this microbiota. It has now become evident that our health is meticulously regulated and affected by our gut microbiota. Gut microbiota regulates our health directly by secreting biologically active substances such as vitamins, essential amino acids, lipids, and indirectly by modulating metabolic processes and the immune system.

Gut microbiota and aging

We acquire our initial dose of microbiota from our mothers during the birthing process. This microbiota then keeps evolving at each stage of our life. As adults, each of us has a unique gut microbiota, something like a unique fingerprint of each individual. The uniqueness of gut microbiota can be attributed firstly to our genetics and secondly to the unique and different habits and lifestyles each one of us has.

There is a distinct difference in the gut microbiota at infancy, early young, adulthood, and geriatric stages of life. In short, our gut microbiota co-evolves with us.

So, how does our gut microbiota affect our health and longevity?

Our aging microbiota

As we age, the diversity of our microbiota reduces, potentially leading to imbalances in the microbiota ecosystem - known as dysbiosis.

As there is a symbiotic relationship between ourselves and our microbiota, we directly feel any imbalances. A thriving, healthy gut microbiota promotes our health and longevity. As microbiota need certain nutrients, such as folate and choline content to replicate, good nutrition and diet play a central role in shaping healthy gut microbiome.

Imbalanced diet, drugs, environmental toxins, free radical damage due to stress, psychological stressors, and other pro-inflammatory factors are some of the factors that result in gut dysbiosis. Obesity and metabolic disorders have been found to be linked with overuse of antibiotics, and imbalanced diets, (high fat or carbohydrate diets, for example).

Gut dysbiosis triggers chronic low-grade inflammation and innate immune response, resulting in many age-related degenerative diseases and conditions, such as inflammatory bowel disease, obesity, diabetes, cardiovascular diseases, and neurodegenerative diseases.

How A Healthy Gut Affects Covid19

Though COVID-19 is primarily a respiratory disease, the severity of the infection has been found to be strongly related to the gut microbiome. Irrespective of the medication, severe cases COVID-19 patients have been found to be in severe dysbiosis, with a significantly lower immune active microbe population, which continued to be the case after recovery.

This suggests that a well balanced, healthy gut microbiome more readily defends ourselves against infections and illness. Maintaining a diverse microbiota thus seems to be critical for long, healthy life.

"Health is a state of complete harmony of the body, mind and spirit. When one is free from physical disabilities and mental distractions, the gates of the soul open." – B.K.S. Iyengar

Dr. Amita Joshi

Dr. Joshi is a Pharmaceutical formulation scientist with a keen interest in scientific communication. She has several peer-reviewed international publications, book chapters and patents to her credit and been a recipient of various research awards. Her areas of interest include lipid-based formulations, lymphatic delivery, medicated contact lenses and infectious diseases.

References:

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• Kim, S., & Jazwinski, S. M. (2018). The Gut Microbiota and Healthy Aging: A Mini-Review. Gerontology, 64(6), 513–520. https://doi.org/10.1159/000490615.
• Pérez Martínez, G., Bäuerl, C., & Collado, M. C. (2014). Understanding gut microbiota in elderly's health will enable intervention through probiotics. Beneficial microbes, 5(3), 235–246. https://doi.org/10.3920/BM2013.0079.
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