A study reveals that eating a Mediterranean diet promotes the type of gut bacteria which is linked to healthy aging in older people and also reduces those bacteria which cause harmful inflammation.
The findings of this study are published in the journal, Gut.
The researchers said as aging is associated with structural changes, deteriorating functions of the body and increasing inflammation, which indicates the onset of frailty. This diet act on gut microbes in such a way as to harness the onset of physical frailty and also the cognitive decline in older age.
The previous study suggests that a restrictive diet that is commonly used by older people, particularly those who are in long term residential care, reduced the types and range of gut bacteria and helps the early onset of frailty.
The researchers, therefore, wanted to examine the effects of this diet whether it maintains the gut microbes in older people and promotes the retention or proliferation of those gut bacteria which are associated with healthy aging.
Researchers analyzed the gut bacteria of 612 people with the age ranges from 65 to 79, before and after 12 months of either eating usual diet (n=289) or a Mediterranean diet (n-323) which is rich in fruits, nuts, vegetables, olive oil, fish, legumes and low in red meat and saturated fats and specially customized for older people (NU-AGE diet).
The participants of the study belong to five different countries: Italy, France, Netherlands, UK, and Poland. Among them 28 were frail, 151 were on the verge if frailty and 433 were not frail.
Sticking to this diet for 12 months was associated with the various beneficial changes to the bacteria in the gut.
It was associated with driving the loss of bacterial diversity and increase the types of bacteria which were previously associated with various indicators of reduced frailty like hand grip, walking speed, improved brain functions such as memory and with the less production of harmful inflammatory chemicals.
The more detailed study revealed that changes in gut microbiome were associated with the increased amount of bacteria producing beneficial short-chain fatty acids and decreased amount of bacteria producing bile acids, who’s overproduction may lead to bowel cancer, insulin resistance, and fatty liver.
The bacteria which proliferated in response to the Mediterranean diet acted as the ‘keystone’ species, critical for the stable gut ecosystem, pushing out those bacteria which were associated with the frailty indicators.
The changes were mainly driven by the increase in dietary fiber and linked with vitamins and minerals specifically including C, B6, B9, potassium, copper, iron, magnesium and manganese.
These findings were not dependent on the person’s age or BMI, both of these two factors influence the make-up of the gut microbiome.
As there were some differences in the make-up of every person’s gut microbiome, depending on the country, the overall response of this diet after 12 months was the same and consistent, irrespective of their nationalities.
The researcher said that the outcomes of this study can’t establish the causative role of the microbiome in health. They said the interplay of diet, host health and microbiome is one of the complex phenomena influenced by various factors.
The outcomes of this study highlighted some of the rules of this three-way interplay, different factors such as BMI, age, disease status, and initial dietary patterns play an important role in determining the success of these interactions.
This study might prove beneficial therapeutic agents to prevent the early onset of frailty.