After helping us navigate the internet, buy anything with a single click and pay anyone in the world in mere seconds, the interests of many a tech billionaire is converging on one thing – ways to extend the human lifespan.
But peer a little deeper into the study of longevity and you see that most of the research in the so-called ‘anti-ageing’ race does not look at just helping us live longer, but also at how we can live healthier for longer.
This means keeping heart disease, Alzheimer’s and Dementia and a whole host of other age-related conditions at bay for longer than possible today. While some of it might require us to find cures, one theme that’s fast emerging is the central role of the gut in ageing.
Implicated in everything from heart disease and neurological functioning, the gut microbiome – the colony of trillions of microbes living in each of our guts – may hold the key to prolonging healthy lifespan. But the best part, these benefits may not be limited to those who can afford fancy treatments or expensive medication, just a healthy balanced diet and lifestyle modifications.
Research is increasingly showing that as we age, our gut microbiomes become more unique. For the most of adulthood the microbiome remains stable, so scientists immediately began looking at it to understand whether this could be linked with why we develop disease as we age.
“With age, if there is no proper nutrition and complications such as stress, diabetes and non-communicable diseases are not managed, gut microbe growth can be affected negatively,” says Dr Yogita Bhatt, lecturer at the department of food technology, Ramaiah University of Applied Sciences.
A study published by a group of US researchers in February 2021 found that the state of the gut microbiome reflected patterns of healthy ageing and could even serve to predict an individual’s lifespan.
Studying the microbiomes of over 9,000 individuals the study found that there was a decrease in the species of good bacteria. These were the type that break down fibre and starch in the gut to release short-chain fatty acids that serve as the precursors to many important neurotransmitters.
They concluded that retaining a diverse and unique gut microbiome into the older ages was linked with living longer.
While these researchers didn’t go into the specifics of why this could happen, Dr Bhatt explains that these microbes perform several functions that keep disease at bay, with one of the best examples being in reducing risk of colorectal cancer.
“Gut microbiota release metabolites in the form of short-chain fatty acids (SCFA) that help to maintain intestinal barrier, mucus production, and protection against inflammation that could cause colorectal cancer,” says Dr Bhatt.
Diversity matters too
Scientists believe that major diseases that reduce life span – obesity, bowel diseases and cardiac diseases – could potentially be controlled through proper regulation of gut microbiota. Work is being done to test therapies targeting the gut microbiome for addressing individual disorders, as well as overall healthy ageing.
Dr Savitha Narasimhaiah, microbiologist and founder at Medicuality Healthcare Services, a Hyderabad-based company that provides accreditation to hospitals and healthcare firms, says that the gut microbes help to produce three main types of short chain fatty acids – acetate, propionate and butyrate.
“Butyrate is responsible for maintaining oxygen balance in the gut, while propionate is known to control gut hormones responsible for appetite and gluconeogenesis (breaking down carbohydrates to glucose). Acetate plays a role in cholesterol metabolism and appetite regulation” Dr Narasimhaiah says.
A reduction in the diversity of gut microbes has been observed in overweight individuals, those suffering from inflammatory bowel disease, psoriatic arthritis, type 1 and 2 diabetes and arterial stiffness. “Consequently, diversity seems to generally be a good indicator of a healthy gut,” she adds.
How the elderly can improve their microbiomes
One of the best ways to improve gut health according to doctors and researchers is by taking prebiotic supplements of specific strains of bacteria such as Bifidobacteria. The other is ensuring that one eats a balanced diet consisting of various types of foods.
“A diet consisting of variety of food types can lead to a more diverse microbiome, hence it is important to eat a variety of foods at every chance,” says Dr Bhatt.
Additionally, a diet rich in fibre is known to help with the growth of good bacteria while avoiding growth of disease-causing strains.
Other proven methods to improving gut health include consumption of fermented foods, eating whole grains instead of processed grains, and eating a plant-based diet. Studies have also pointed out that plant-based diets lead to reduced levels of disease-causing bacteria and lower cholesterol levels.
While we’re still a little while away from microbiome-based therapies to treat conditions, the millions of dollars being pumped into this space is speeding up innovation. Scientists are hopeful that one of the key aspects of healthy ageing may lie in modulating the gut, and so are billionaires such as Sergey Brin, Jeff Bezos, and Peter Theil.