There have been conflicting ideas about the gut microbiome and its link to healthy aging, Dr. Gibbons, associate professor at Institute for Systems Biology, told the audience in London on Dec. 13 during his presentation on identifying microbiome-mediated drivers of healthy aging.
One idea is that gut changes with age are harmful and unavoidable, so the best approach is to slow them down. The other is that the healthiest people show more dynamic gut changes late in life.
However, this raised a key question for Dr. Gibbons and his fellow researchers: “Are we simply managing decline, or is there a distinct ‘healthy aging’ signature in the gut?”
Healthy aging linked to dynamic gut microbiome changes
Dr. Gibbons explained that recent research found that the microbiota adapted to the changing body as one aged, and those adaptations seemed compensatory or beneficial.
Analysis in older cohorts revealed that when participants were separated by health status, e.g. less healthy versus more healthy, it was actually the healthier group whose microbiomes were the most dynamic.
“Their microbiomes were changing and diverging from the composition typically seen in youth,” he said. “When we stratified by health status using measures like walking speed, self-reported health, medication burden and life-space mobility, a clear pattern emerged: Healthy older individuals showed increasing microbiome uniqueness with age, while less healthy individuals did not.
“In fact, those whose microbiomes still resembled a ‘younger’ composition tended to fare worse. The individuals whose microbiomes continued to change appeared to be the healthier group.”
How gut microbiome optimization supports healthy aging
Dr. Gibbons said that the anti-aging rhetoric could be harmful when it comes to the gut microbiome, and that a different attitude is needed.
“Many anti-aging approaches focus on rejuvenation, making the body resemble its physiological state in one’s twenties—but that may not be appropriate for the gut, unless you can truly make an aging gut functionally ‘young’ again,” Dr. Gibbons said.
He stressed that if functional rejuvenation is not possible, the focus must shift to adapting the microbiota to the aging environment and optimizing it for healthy aging.
He explained that optimizing the microbiome could positively impact the interpretation of nutrition solutions for healthy aging. Anti-inflammatory metabolites, such as butyrate, which are produced by the microbiota and are beneficial in older adults, tend to increase in healthier older people, and therefore some probiotics can target that function, he said.
Akkermansia is also beneficial for metabolic health and declines in less healthy older individuals, making it another supplementation target, as is Bifidobacterium, which is associated with healthy aging and diminishes in less healthy people, making it a clear probiotic candidate.
Predicting microbiome outputs for better health
As each person’s microbiota responds differently to dietary inputs, a personalized strategy will be necessary, Dr. Gibbons explained, noting that some metabolic profiling models are allowing researchers to predict individualized outputs.
“We recently obtained data showing that for short-chain fatty acids, key health-promoting compounds produced by the microbiome, we can quantitatively predict outputs with good accuracy,” he said.
The next steps will be to conduct a prospective clinical trial using personalized, microbiome-informed nutritional interventions and show that they outperform a standard approach, such as the Mediterranean diet.
“Until we have that evidence, these interventions won’t make it to market,” he said. “So the next step is building that scientific foundation.”
