Probiotics in the Fight against Alzheimer’s Disease

Many health conditions once thought to be irreversible improve or are even resolved by looking to the gut for answers. Changes in gut bacteria can cause inflammation that in turn causes numerous problems. Now scientists are finding that loss of diversity in gut bacteria can hasten brain degeneration, the telltale sign of Alzheimer’s disease, which is linked to brain inflammation.

Studies that focused on populations throughout the world where gut organisms were measured and monitored showed a decreased prevalence of Alzheimer’s disease in communities where damage to gut organisms was low. Scientists have taken information like this and are looking at the situation in a different light. Since damage to gut bacteria results in brain inflammation and deterioration, could restoration of good bacteria using probiotics help those with Alzheimer’s?

A 2016 study published in Frontiers in Aging Neuroscience studied a group of 60 elderly Alzheimer’s patients for 12 weeks. Participants underwent a mini-mental status exam (MMSE), a standardized cognitive assessment used worldwide that measures mental function. They were each given a highly sensitive c-reactive protein (hs-CRP) blood test, which is a powerful marker of inflammation. Half the participants were given a placebo, while the other half consumed a probiotic milk containing the probiotic species Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium bifidum, and Lactobacillus fermentum. After 12 weeks, the tests were repeated.

The placebo group showed an increase in the inflammation marker hs-CRP by 45%. In the group taking the probiotic, hs-CRP declined by 18%, indicating a dramatic reduction in inflammation. Over the 12 weeks, patients in the placebo group continued to decline mentally. This was reflected in their MMSE score, which dropped from 8.47 to 8.00. In contrast, the group on the probiotics did not decline mentally, but actually experienced an improvement, with MMSE scores going from 8.67 to 10.57.

This study and others indicate that inflammation is determined by the health and diversity of gut bacteria. The finding regarding the benefits of probiotics for Alzheimer’s disease has major implications in terms of brain health, function, and disease resistance. Probiotics can be explored as treatment for other conditions associated with inflammation such as Parkinson’s disease, multiple sclerosis, diabetes, coronary artery disease, and even cancer.