New Delhi: Greater diversity in gut bacteria may be associated with stronger hormonal and perceived stress responses, according to a new study.

Researchers said the gut microbiome — comprising microorganisms in the digestive system — plays a key role in metabolism, immune function and regulation of the body's stress response.

The study, conducted on 74 healthy adults, found that individuals with higher microbial diversity showed greater cortisol levels and subjective stress reactivity during a standardised stress test. The findings have been published in the journal Neurobiology of Stress.

However, experts noted that a stronger acute stress response is not necessarily harmful and may help individuals adapt better to challenges.

The research also found that the gut bacteria's ability to produce metabolic compounds, such as short-chain fatty acids, was linked to stress responses. Higher production of butyrate was associated with increased stress reactivity, while higher propionate levels were linked to lower reactivity.

The findings suggest that the gut microbiome — influenced by diet and lifestyle — may play a role in shaping how the body responds to stress.

Researchers said the relationship between gut bacteria and stress is complex and requires further investigation.