Scientists just discovered what coffee is really doing to your gut and brain - ScienceDaily

Researchers report that both caffeinated and decaffeinated coffee reshape gut bacterial communities in ways linked to improved mood, lower stress and, in some analyses, better learning and memory. The recent report associating egg consumption with reduced Alzheimer’s risk reinforces the idea that multiple everyday foods and beverages could influence cognition through the gut–brain axis. However, study designs and evidence strength vary, and randomized trials are needed to establish whether these dietary factors causally improve brain health.