In people with Alzheimer’s disease, the underlying changes in the brain associated with dementia typically begin many years — or even decades — before a diagnosis. While pinpointing the exact causes of Alzheimer’s remains a major research challenge, they likely involve a combination of genetic, environmental, and lifestyle factors. Now an NIH-funded study elucidates the role of another likely culprit that you may not have considered: the human gut microbiome, the trillions of diverse bacteria and other microbes that live primarily in our intestines [1].
Earlier studies showed that the gut microbiomes of people with symptomatic Alzheimer’s differ from those of healthy people with normal cognition [2]. What this new work advances is that these differences arise early on in people who will develop Alzheimer’s, even before any obvious symptoms appear.
The science still has a way to go before we’ll know if specific dietary changes can alter the gut microbiome and modify its influence on the brain in the right ways. But what’s exciting about this finding is it raises the possibility that doctors one day could test a patient’s stool sample to determine if what’s present from their gut microbiome correlates with greater early risk for Alzheimer’s dementia. Such a test would help doctors detect Alzheimer’s earlier and intervene sooner to slow or ideally even halt its advance.
Read more about these new findings at www.nia.nih.gov
