Can a Mediterranean Diet Change the Gut Microbiome and Support Healthy Ageing?
Summary ID04-MB-RS-00032
Research Summary
Original Publication
Mediterranean diet intervention alters the gut microbiome in older people reducing frailty and improving health status: the NU-AGE 1-year dietary intervention across five European countries
Journal
Gut, .
- Category
- 04Microbiome & Longevity
- Evidence
- Randomized controlled trial
- Summary Type
- Core
What Was Studied?
The NU-AGE study was a 12-month randomized, multicentre, controlled dietary intervention in adults aged 65–79 years.
This microbiome analysis included 612 non-frail or pre-frail participants from Poland, the Netherlands, the United Kingdom, France and Italy. Microbiome data were available at baseline and after 12 months.
Of the 612 participants, 323 followed a Mediterranean-style diet adapted for older adults and 289 were controls.
The diet included more vegetables, legumes, fruit, nuts, olive oil and fish, with less red meat, saturated fat and some dairy products.
Researchers examined changes in the gut microbiome and their associations with frailty, physical function, cognitive function and inflammation.
They also estimated potential microbial metabolic activity from microbiome composition.
Key Findings
The Mediterranean diet changed specific parts of the gut microbiome
Greater adherence to the Mediterranean diet was associated with changes in specific bacterial groups, including Faecalibacterium prausnitzii, Roseburia, Eubacterium and Anaerostipes hadrus.
Several of these bacteria are known producers of short-chain fatty acids.
The intervention did not produce a general increase in microbiome diversity. However, greater dietary adherence was associated with a smaller loss of diversity over 12 months.
Similar diet-associated microbiome changes were identified across the five countries despite differences in baseline diet and microbiome composition.
Microbiome changes were associated with healthier ageing
Bacterial changes associated with greater Mediterranean diet adherence were linked to lower frailty and better cognitive function.
They were also associated with better physical function, including walking speed and hand-grip strength, and lower levels of C-reactive protein (CRP) and interleukin-17.
These associations remained after accounting for age and body mass index.
The study found associations between microbiome changes and these health measures. It did not establish that the microbiome changes caused them.
The study identified possible changes in microbial metabolism
The diet-associated microbiome was linked to higher predicted production of short-chain and branched-chain fatty acids and lower predicted production of secondary bile acids, p-cresols, ethanol and carbon dioxide.
These metabolic changes were predicted from microbiome composition and were not directly measured.
The researchers also found that bacteria responding positively to the Mediterranean diet occupied central positions within microbial networks. Bacteria associated with frailty were more peripheral.
Why It Matters for Longevity
The study shows that the gut microbiome remains responsive to sustained dietary change in older age.
Changes associated with the Mediterranean diet were also linked to lower frailty, better physical and cognitive function, and lower inflammation.
The microbiome may therefore represent one biological pathway connecting long-term diet with healthy ageing. The study did not determine whether microbiome changes were responsible for the observed health effects.
Clinical Perspective
The study supports long-term dietary modification as a practical way to influence the gut microbiome in older adults.
The microbiome response involved multiple bacterial groups and was associated with several measures of healthy ageing.
For clinical interpretation, microbiome findings should be considered together with diet, health status and other clinical factors. The study does not support targeting a single bacterial species based on these findings.
Key Takeaway
A 12-month Mediterranean diet intervention changed specific components of the gut microbiome in older adults. These changes were associated with lower frailty, better cognitive function and lower inflammation, supporting the microbiome as one possible pathway linking diet with healthy ageing.
Reviewed and Summarized by
Source Publication
- Title:
- Mediterranean diet intervention alters the gut microbiome in older people reducing frailty and improving health status: the NU-AGE 1-year dietary intervention across five European countries
- Authors:
- Ghosh TS et al
- Journal:
- Gut, 2020.
