Lead researcher Mary Ni Lochlainn, King’s College London (KCL), and colleagues asked whether adding a daily prebiotic to a modest protein supplement and light resistance exercise could affect cognition in older twins.
The team enrolled 36 pairs, each aged 60 or older, and assigned one twin to inulin plus fructooligosaccharides while the co-twin received a placebo, all under double blind conditions.
Everyone received the same branched chain amino acid protein powder and simple at home strength moves.
The 12 week protocol ran remotely using video visits, online questionnaires, and posted kits for cognitive testing and stool samples.
The twin design reduced genetic and early environmental noise. That choice made any between twin differences more likely to reflect the supplement rather than family background or shared habits.
Fructooligosaccharides and memory
The prebiotic group scored higher on a combined cognition factor and made fewer errors on the PAL test, a visual paired associated task sensitive to early Alzheimer’s related change.
That pattern fits with decades of work showing PAL detects subtle episodic memory problems before many standard clinic scales do.
“We are excited to see these changes in just 12 weeks. This holds huge promise for enhancing brain health and memory in our ageing population,” said Dr. Lochlainn.
The specific test improvement matters because paired associates learning taps the ability to form new connections between locations and patterns.
That is a core function that erodes early in Alzheimer’s, so even small gains on this task are notable in people over 60.
Open access paper:
Effect of gut microbiome modulation on muscle function and cognition: the PROMOTe randomised controlled trial
Abstract
Studies suggest that inducing gut microbiota changes may alter both muscle physiology and cognitive behaviour. Gut microbiota may play a role in both anabolic resistance of older muscle, and cognition. In this placebo controlled double blinded randomised controlled trial of 36 twin pairs (72 individuals), aged ≥60, each twin pair are block randomised to receive either placebo or prebiotic daily for 12 weeks. Resistance exercise and branched chain amino acid (BCAA) supplementation is prescribed to all participants. Outcomes are physical function and cognition. The trial is carried out remotely using video visits, online questionnaires and cognitive testing, and posting of equipment and biological samples. The prebiotic supplement is well tolerated and results in a changed gut microbiome [e.g., increased relative Bifidobacterium abundance]. There is no significant difference between prebiotic and placebo for the primary outcome of chair rise time (β = 0.579; 95% CI −1.080-2.239 p = 0.494). The prebiotic improves cognition (factor score versus placebo (β = −0.482; 95% CI,−0.813, −0.141; p = 0.014)). Our results demonstrate that cheap and readily available gut microbiome interventions may improve cognition in our ageing population. We illustrate the feasibility of remotely delivered trials for older people, which could reduce under-representation of older people in clinical trials. ClinicalTrials.gov registration: NCT04309292
https://www.nature.com/articles/s41467-024-46116-y
