Individuals with dementia show a different makeup in the bacteria dwelling in their guts, a recent study found. These results raise questions about whether bacteria play some role in the brain disease. According to the study, bacteria appear to affect a range of bodily functions, from immune defenses to the production of vitamins, anti-inflammatory compounds and even chemicals that relay messages among brain cells. However, the study does not prove that gut bacteria directly contributes to, or protects against dementia. “The study found only that a group of dementia patients had different gut microbes from dementia-free adults. You'd expect to see a lot of differences between those two groups of people,” said Mary Sano, PhD, director of the Alzheimer's Disease Research Center at Icahn School of Medicine at Mount Sinai. “It's very possible that the dementia was the cause of the gut differences, not the result. For example, diet is critical in the makeup of gut bacteria, and people with dementia often have changes in appetite and end up malnourished,” added Dr. Sano, who was not involved in the research. Whether microbes have any direct effect on dementia risk remains unknown.
— Mary Sano, PhD, Director, Alzheimer’s Disease Research Center, Icahn School of Medicine at Mount Sinai, Associate Dean, Clinical Research, Professor, Psychiatry, The Mount Sinai Hospital
Additional coverage: HealthDay