Water supports normal digestion and helps fiber do its job. When fluid intake is too low, the colon can absorb more water from stool, making it harder and more difficult to pass.
What to keep in mind
More is not always better. Fluid needs change with body size, activity, climate, pregnancy, illness, and diet. Pale yellow urine and normal thirst can be practical signals for many healthy adults.
Increase fiber gradually and pair it with adequate fluid. People with heart, kidney, or liver conditions should follow individualized medical advice about fluid intake.