Probiotics found to benefit cognition of Alzheimer’s patients

A study published in the journal Frontiers in Ageing Neuroscience has suggested that consuming probiotics can help improve thinking and memory skills among people with Alzheimer’s disease.

The 12-week study followed 52 men and women with Alzheimer's disease and saw half consume a daily 200ml milk drink enriched with four probiotic bacteria (Lactobacillus acidophilus, L. casei, L. fermentum, and Bifidobacterium bifidum). The other half of the group consumed a daily milk drink with no probiotics.

The findings indicated a ‘moderate but significant’ improvements in the cognitive function scores of the group that drank milk containing probiotic bacteria.

The cognitive function of the participants were measured using a standardised questionnaire known as the Mini Mental State Examination (MMSE). The test involved tasks such as citing the date, counting backwards from 100 in sevens, naming objects, repeating a phrase and copying a picture.

For the treatment group, the average score on the MMSE questionnaire significantly increased, from 8.7 to 10.6, out of a maximum of 30. Meanwhile, the non-treatment group saw no improvements with an average MMSE score beginning at 8.5 and ending at 8.0.

Professor Mahmoud Salami, senior author on the study from Kashan University in Tehran, Iran, said: "In a previous study, we showed that probiotic treatment improves the impaired spatial learning and memory in diabetic rats, but this is the first time that probiotic supplementation has been shown to benefit cognition in cognitively impaired humans."

“These findings indicate that change in the metabolic adjustments might be a mechanism by which probiotics affect Alzheimer's and possibly other neurological disorders. We plan to look at these mechanisms in greater detail in our next study."

Dr Rosa Sancho, head of research at Alzheimer's Research UK, commented: "The brain is often viewed as being separate from the rest of the body but scientists are understanding more about how changes in the body can impact upon the brain too.

"This new study raises interesting questions about the link between the gut and the brain, and their association with Alzheimer's disease. The improvements in memory and thinking seen in people with Alzheimer's disease in this study will need to be repeated in much larger studies before we can understand the real benefits of probiotics for the brain.

"We don't fully understand how changes in the gut could be affecting the brain, and Alzheimer's Research UK is funding research in this area to improve our understanding of this link."