Can stress, low caloric intake, high anxiety, and sedentary lifestyle contribute to urinary frequency with pale urine, and is Pedialyte (electrolyte solution) effective in managing these symptoms, or is diabetes insipidus a more likely cause?

Stress and Malnutrition as Cause of Urinary Symptoms

Your urinary frequency with pale urine is most likely caused by your severe caloric restriction (300 calories/day) and inadequate fluid/electrolyte intake, not diabetes insipidus, and Pedialyte helped because it corrected your electrolyte imbalance and provided osmotic drive for water retention.

Why Your Lab Values Point Away from Diabetes Insipidus

Your laboratory results actually argue against diabetes insipidus:

• Serum osmolality of 300 mOsm/kg is only mildly elevated (normal 275-295), not the marked elevation typically seen in untreated diabetes insipidus 1, 2
• Serum sodium of 143 mEq/L is normal (normal 135-145), whereas diabetes insipidus typically causes hypernatremia >145 mEq/L 1, 2
• Urine osmolality of 170 mOsm/kg, while dilute, is not maximally dilute - true diabetes insipidus produces urine osmolality <100 mOsm/kg 1, 2
• Urine sodium of 39 mEq/L indicates some sodium conservation, which would be impaired in severe diabetes insipidus 3

The Real Culprit: Starvation Ketosis and Electrolyte Depletion

Your ketones of 5 mg/dL indicate starvation ketosis from eating only 300 calories daily, which creates a complex metabolic state:

• Severe caloric restriction causes muscle breakdown and electrolyte losses that impair normal kidney concentrating ability 4
• Drinking only water without electrolytes creates a dilutional state where your kidneys must excrete excess free water, producing pale, dilute urine 4
• Stress and anxiety increase cortisol, which promotes water excretion and can worsen electrolyte imbalances 3
• Sedentary lifestyle reduces muscle mass, further compromising electrolyte stores 5

Why Pedialyte Worked

Pedialyte contains balanced electrolytes (sodium, potassium, chloride) and glucose that:

• Provide osmotic particles that help your kidneys retain water rather than excrete it as dilute urine 4
• Restore sodium and chloride balance - your chloride of 107 mEq/L is at the upper limit of normal (98-107), suggesting prior depletion that Pedialyte corrected 4
• The glucose in Pedialyte provides calories and helps sodium absorption in the gut, improving overall fluid retention 4

Critical Action Steps Before Your 24-Hour Urine Collection

You must address your nutritional crisis immediately:

• Increase caloric intake to at least 1200-1500 calories daily to prevent further metabolic deterioration 4
• Continue drinking water but add electrolyte-containing fluids (broths, electrolyte solutions) to maintain balance 4
• Your eGFR of 99 mL/min/1.73m² is normal, indicating your kidneys are functioning well despite the metabolic stress 6

What the 24-Hour Urine Collection Will Show

If diabetes insipidus were present, you would expect:

• 24-hour urine volume >3 liters (true polyuria) 5
• Persistently low urine osmolality <200 mOsm/kg throughout the collection 1, 2
• Inability to concentrate urine even when dehydrated 1, 2

More likely, your collection will show:

• Variable urine volumes depending on fluid and electrolyte intake 5
• Improved urine concentration when you consume adequate electrolytes 4
• Normal to mildly increased total urine output reflecting your high water intake without adequate solute 5

Addressing Your Underlying Stressors

Grief, anxiety, and stress contribute to your symptoms through multiple mechanisms:

• Stress-induced cortisol elevation promotes water excretion and can cause urinary frequency 3
• Anxiety often leads to increased fluid intake (nervous drinking), creating a cycle of frequency 5
• Sedentary behavior from depression reduces normal fluid distribution in the body 5

Behavioral modifications that will help:

• Regulate fluid intake to 1.5-2 liters daily rather than excessive water consumption 5
• Avoid drinking large volumes in the evening to reduce nocturia 5
• Gradually increase physical activity to improve overall metabolic function 5

Common Pitfall to Avoid

Do not continue severe caloric restriction while awaiting diabetes insipidus workup - your metabolic state from starvation is likely causing or significantly contributing to your urinary symptoms, and continued restriction will confound test results and worsen your health 4. The combination of ketones, electrolyte abnormalities, and urinary frequency in the context of severe malnutrition points to a metabolic cause rather than primary diabetes insipidus 4.