How Your Gut Health Shapes Immunity and Ageing

Scientists studying human ageing are looking closely at the gut and its trillions of microorganisms, which form what is known as the gut microbiome. Dr Sandip Banerjee, founder of Pelvinic Micro-Hospital, senior laparoscopic colorectal surgeon, proctologist, and bariatric surgeon based in New Delhi, shared key insights on how this ecosystem affects digestion, immunity, and healthy ageing.

The Gut Microbiome

Every person has a gut microbiome that is highly individual and can be changed by diet, environment, lifestyle, medicines, and health conditions. Even with these differences, many people share similar microbial functions, which researchers call a functional core gut microbiome. While adult gut bacteria can stay relatively stable over time, the system is an ecosystem that adapts to new conditions. As people grow older, the composition and functions of these microbes change, and researchers have found distinct differences between healthy older adults and those experiencing frailty.

Immunity And Brain Links

The gut microbiome helps regulate immune activity. When it becomes disrupted—a state called dysbiosis—it may link to changes in inflammation and other ageing processes, though dysbiosis is not seen as the root cause of age-related disease. Furthermore, the gut connects to the brain through what experts call the gut-brain axis, where microbial signals touch hormonal and immune pathways to influence cognition and overall health. Diet remains a key factor in shaping these microbes, with plant and fibre-rich diets boosting health-linked activity, though no single food or supplement guarantees longevity.

Context

The gut microbiome functions as a complex internal ecosystem made up of bacteria, fungi, and other microbes living in the digestive tract. Medical research increasingly focuses on these communities because they interact closely with human metabolic and immune systems as people grow older.