Mediterranean diet and microbiome – another piece in the puzzle

A new study added another piece to the puzzle of the positive health effects of the Mediterranean diet: the results of this intervention showed that eating a Mediterranean diet for one year altered the microbiome of elderly individuals in ways which improved brain function and contributed to a longer life expectancy.

Ageing is associated with the deterioration of various body functions and inflammation, resulting in the start of frailty. Such onset of frailty is associated with changes in the gut microbiome that are linked with a less diverse diet.

The current study analysed the gut microbiome of 612 elderly individuals from France, Italy, the Netherlands, Poland and the UK, 323 of them, then received a Mediterranean-type diet for 12 months (NU-AGE Med diet).  Even though this Med diet was designed for elderly individuals, it contained lots of fruits, vegetables, nuts, legumes, olive oil, fish and moderate consumption of alcoholic beverages. The remaining 65-79 year-olds of the study served as control group and continued eating as they always did.

After one year, those who adhered to the Med diet showed beneficial changes to the microbiome of their digestive system. The loss of bacterial diversity was slowed down and less potentially harmful inflammatory markers (i.e. C-reactive protein, interleukin-17) were observed. At the same time, the researchers observed a growth of beneficial gut bacteria linked to improved memory and brain function. The diet seemed to boost bacteria species which are critical for a stable gut “ecosystem” and also reduced signs of physical weakness such as walking speed and hand grip strength.

The findings were similar and consistent, independently where the participants came from. Furthermore, neither their weight nor age, which both influence the unique make up of an individual’s microbiome, seemed to matter. The authors concluded that by improving the usual diet, the gut microbiome can be improved in a way which has the potential to promote healthier ageing.

This study is part of a larger randomized controlled trial with 1200 participants called NU-AGE (European Project on Nutrition in Elderly People) which started in 2012. Previous results from this ongoing study showed that those following the diet closely had improved cognitive ability and a reduced rate of bone loss in individuals with osteoporosis as well as improved blood pressure.

Definitions:

Moderate consumption of alcoholic beverages in the NU-AGE Med diet: 1 drink for women and 2 drinks for men; 1 drink = 10g of alcohol

Ghosh, TS et al, 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, Gut 2020;0:1-11.

https://www.doi:10.1136/gutjnl-2019-319654 

More information about the final NU-AGE conference:

https://www.euagenda.eu/2016/4/5/Final-NU-AGE-Conference