Affordable Supplements Reshape Understanding of Gut and Brain Connection

Recent findings are prompting scientists to reconsider the relationship between the gut and brain, thanks to economical daily supplements.

A twin study published in Nature Communications in 2024 revealed that daily consumption of protein and prebiotic supplements could enhance memory performance in individuals over 60. This study has quickly gained traction, with nearly 100 citations and has led to new clinical trials exploring how certain supplements might offer protection against dementia.

Later that same year, researchers at Wageningen University in the Netherlands initiated the PRECODE clinical trial. This trial, focusing on the gut-brain health implications of prebiotics in older adults showing signs of cognitive decline, is the first to examine the combined effects of three different dietary fibers: chicory inulin, resistant dextrin, and seaweed polysaccharide, alongside a placebo (maltodextrin).

For a span of 26 weeks, participants aged 60 and older consumed these fibers twice daily, either mixed into water, tea, or coffee. Their cognitive abilities and brain health were monitored through regular scans and tests. We’ll receive more insights when the trial wraps up in 2027.

Interestingly, inulin, a fiber categorized as a fructan, was previously linked to cognitive improvements in the aforementioned twin study.

During that controlled trial, researchers utilized two budget-friendly plant-fiber prebiotics commonly available over the counter. The second one, fructooligosaccharide (FOS), is often utilized as a low-calorie sweetener.

To assess how these supplements influenced cognitive functions in older adults, a team from King’s College London enrolled 36 pairs of twins, with participants aged 60 years and above. The twins were randomly assigned; one received a daily prebiotic mixed into protein powder, while the other received a placebo.

Results showed the twins who inadvertently consumed inulin or FOS generally achieved better scores on cognitive tests three months later. Additionally, these daily fiber supplements appeared to bring about slight changes in the gut microbiome among the twins.

For instance, the presence of beneficial Bifidobacterium was observed to be greater among those taking inulin or FOS. Previous research on mice indicates that Bifidobacterium can alleviate cognitive impairments by influencing gut-brain interactions.

Mary Ni Lochlainn, a researcher in geriatric medicine at King’s College London, expressed enthusiasm about the changes noted in just 12 weeks. “This holds huge promise for enhancing brain health and memory in our aging population,” she stated in 2024.

“Exploring the gut-brain axis may yield new pathways for healthier living as we age,” she added.

King’s College London possesses the UK’s largest adult twin registry, allowing for valuable insights regarding the impact of genetics and environment on health through twin studies.

Previous studies on rodents suggest that high-fiber supplements like inulin and FOS can nourish the microbiome in the colon, promoting the growth of beneficial bacteria.

Some of these bacteria are also associated with enhanced cognitive abilities in both mice and humans.

Growing evidence underscores the relationship between the gut and brain, as research continues to demonstrate connections to conditions like Alzheimer’s and Parkinson’s disease. Some scientists have started referring to the gut as the body’s “second brain.”

However, the exact mechanics of how these two systems collaborate remain largely unknown.

The twin study hints at the potential for specific “brain foods” to combat cognitive decline, complementing existing evidence that certain nutrients might slow mental deterioration in aging individuals.

Geriatrician Claire Steves from KCL highlighted the potential for these fiber supplements to reach a wide audience, especially during financially challenging times. “They are safe and accessible,” she noted.

The next phase involves determining whether the positive effects endure over extended periods and across broader populations. That is the objective of the PRECODE trial, which aims to deliver a detailed examination of the microbiota-gut-brain connection in older adults facing cognitive risks.

The twin study was available in Nature Communications.