Overview
- Published Friday in Nature Communications, a study of 62 healthy adults found that daily coffee reshapes specific gut microbes, body chemicals, mood, and thinking skills.
- Participants paused coffee for two weeks, then spent three weeks on a double-blind reintroduction of either caffeinated or decaffeinated coffee.
- Both versions shifted targeted bacterial species and lowered perceived stress and depression, while caffeinated coffee reduced anxiety and salivary cortisol and decaf improved episodic memory and sleep quality.
- The trial tied coffee to changes in inflammatory proteins, with both types lowering interleukin‑6 after intervention and decaf showing rises in C‑reactive protein and TNFα in some measures.
- Researchers say polyphenols in coffee likely explain many shared effects and they call for larger, longer trials given the small sample, short protocol, self-reported mood data, and limited diet control.