Gut microbiome linked to mild cognitive impairment

Yoghurt and parmesan cheese could be the answer to preventing memory loss as people age, a new study suggests. Scientists from the University of North Carolina in the US have found a healthy gut microbiome can improve memory.

They say that consuming foods high in the probiotic Lactobacillus rhamnosus GG (LGG) for three months is enough to change the mix of bacteria in the digestive system. While LGG can be taken as a supplement, it’s also present in foods including sauerkraut and kimchi.

Some 169 people aged between 52 and 75 took part in the research, with half displaying symptoms of mild cognitive impairment and others having healthy brains. While some participants were given the probiotic, others were administered a placebo.

Gene sequencing was then used to analyse the gut bacteria of all those involved. They discovered that participants with mild cognitive impairment had higher levels of a bacteria called Prevotella than those with normal cognitive function.

Such insight into the impact the composition of the gut microbiome has on memory loss could be useful for preventative medicine. Being aware of early indicators allows for interventions to be taken sooner and if that’s a change in diet, then it’s fairly straightforward to implement.

Further to this, the analysis showed that for participants with mild cognitive impairment who were given the LGG probiotic, the amount of Prevotella in their gut decreased over the three months. This correlated with improved scores in cognitive tests.

Mashael Aljumaah, author of the study, said: “The implication of this finding is quite exciting, as it means that modifying the gut microbiome through probiotics could potentially be a strategy to improve cognitive performance, particularly in individuals with mild cognitive impairment.

“Many studies focus on severe forms of cognitive diseases such as Alzheimer's and dementia, but these conditions are more advanced, making them significantly harder to reverse or treat. In contrast, we focused on mild cognitive impairment, which can include problems with memory, language, or judgement.”

Most research into cognitive impairment is in agreement that early intervention is key to slowing the progression of memory loss. Any lifestyle changes, such as eating a balanced diet and exercising regularly, are seen as positive steps that should be taken as people age.