Gut Health Alarms: Subtle Signs Your Digestion Is in Trouble

35. Exaggerated Sensitivity to Caffeine and Alcohol

If you've developed an increased, almost immediate, intolerance to small amounts of caffeine or alcohol, it can be a sign of a compromised gut lining and overworked liver. A healthy gut helps filter and process toxins before they overload the liver. With gut distress, toxins and metabolites (including those from coffee and alcohol) are shunted into the bloodstream faster, leading to exaggerated symptoms like immediate heart racing, anxiety, or a disproportionately fast onset of intoxication. This sudden drop in tolerance indicates your body's major detoxification and barrier systems are running inefficiently.

36. Fissured or Grooved Nails (Beau's Lines)

While you mention brittle nails, horizontal grooves or deep lines (Beau's lines) that appear across your fingernails can be a distinct, retrospective sign of gut distress. These lines form when nail growth temporarily slows or stops due to a major physical stressor or acute nutrient shortage—often caused by a severe gut flare-up or period of extreme malabsorption. Since nails grow slowly, the line you see today reflects a stress event that happened weeks or months ago, providing a physical, time-stamped record that your gut was severely struggling and diverting resources away from growth.