Urine Color When Fasting

Does fasting affect urine?

Urine concentrations of uric acid, citrate, phosphate, sodium, and potassium during fasting were significantly higher than nonfasting. Uric acid supersaturation was accentuated, and calcium phosphate supersaturation was decreased significantly during fasting.

Why is my urine dark when I fast?

This may be especially common when you’re first beginning an intermittent fasting regimen. To stay properly hydrated, drink water throughout the day and monitor the color of your urine. Ideally, it should be a pale lemonade color. A dark-colored urine may indicate you’re dehydrated ( 22 ).