Hunger Hormones Hijacked

Gut bacteria can sway your appetite by influencing ghrelin and leptin — the hormones that signal hunger and fullness. Some bacterial communities appear to nudge ghrelin signaling, leaving you hungry even after you have eaten enough. This happens below conscious awareness, which makes it hard to override by willpower alone.

Some bacteria also release molecules that mimic dopamine signals, sparking cravings for the sugar and fat that feed those same species. Your midnight snack craving may not be entirely your decision — it could be a bacterial demand for the nutrients those microbes prefer.