The gut is central to several age-associated changes. Its role in nutrition is unique, but there is a wealth of evidence highlighting its influence on old age too. The composition of the microbiome – a colony of trillions of bacteria – changes continuously as the body ages. Fortunately, certain dietary guidelines can help the body harvest a healthier microbiome.
Ageing scientists studying longevity hotspots around the world have found ample evidence linking diet to longevity. And the gut is believed to be the stronghold of this relationship.
Ross Austen, Nutrition and Research lead at MOJU, explained: “There are trillions of microwaves that call your gut home and keeping them happy is integral to your health.
“The microbes have several functions; including making vitamins, maintaining a well functioning immune system, creating energy and may even improve your mood via the gut-brain axis.”
The collection of bacteria, which starts at birth, is subjected to several changes over the course of a lifetime.
In older adulthood – approximately after age 60 and 65 – the diversity of the gut microbiota starts to decline.
Research published in the medical journal Nature Metabolism last year, however, found several gut microbiome patterns linked to healthy ageing and increased longevity.
Evidence suggests that previously non-dominant bacteria become enriched while the number of Bifidobacteria drops.
This bacteria, which is rife in the digestive system of babies, is known to prevent infections and function as a probiotic.
In individuals who do reach old age, however, the micro-biome divergence tends to be restored.
Commenting on the findings of the study, the National Institute of Ageing (NIA) explained: “The healthier participants’ blood tests showed lower levels of LDL cholesterol and higher levels of vitamin D, but also more beneficial blood metabolites produced by gut microbes.
“One of these metabolites, tryptophan-derived-indole, has been shown to reduce inflammation and to extend lifespans in mouse studies.”
What’s more, people with greater diversity in microbes were able to walk faster and showed signs of having better overall mobility than their peers.
The NIA added: “Those with less diverse gut environments used more medication and were nearly twice as likely to die during the study period.”
Diet and gut health
Experts suspect that the modern diet, which emphasises foods rich in fat, salt and sugar, could accelerate ageing.
Other foods such as fruits, vegetables, seeds, beans and nuts, on the other hand, are believed to restore the balance of the gut microbiome as the body ages.
One surefire way to diversify the gut microbiome is through diet; with the consumption of probiotics.
Found in fermented foods, like yoghurts, kimchi and kefir, probiotics provide ample bacteria to boost the body’s immune defences.
Previous research has also suggested a Mediterranean-style diet rich in fish, fruit and olive oil may also help people live longer due to its effect on bacteria in our stomachs.
Professor Claudio Franceschi, from the University of Bologna, Italy, said: “Nutritional should let people stay healthy and avoid drugs.”