Could my symptoms of frequent urination with pale urine, hypernatremia, and low urine osmolality be caused by stress, caloric restriction, or high anxiety rather than diabetes insipidus?

Your Symptoms Are Most Likely Due to Severe Caloric Restriction and Stress, Not Diabetes Insipidus

Your laboratory values do not support a diagnosis of diabetes insipidus, and your symptoms are entirely consistent with the physiological consequences of consuming only 300 calories per day (or nothing at all), combined with high stress and anxiety following your recent bereavement.

Why This Is Not Diabetes Insipidus

Your biochemical profile argues strongly against diabetes insipidus:

• Your serum sodium is 143 mmol/L (normal range), whereas diabetes insipidus typically presents with high-normal or elevated serum sodium (>145 mmol/L) combined with inappropriately dilute urine 1, 2
• Your serum osmolality is 300 mOsm/kg (normal to slightly elevated), but not the marked hyperosmolality typically seen in untreated diabetes insipidus 1
• Your urine osmolality of 170 mOsm/kg is dilute, but patients with true diabetes insipidus typically have urine osmolality <200 mOsm/kg combined with serum sodium >145 mmol/L, which you do not have 1, 2
• Your urine sodium of 39 mEq/L indicates ongoing electrolyte losses, but this is consistent with your severe caloric restriction causing metabolic waste excretion, not diabetes insipidus 1

Most importantly: Patients with true diabetes insipidus have an intact, hyperactive thirst mechanism that drives them to drink enormous volumes (typically 3-5+ liters per day) to compensate for urinary water losses 1, 2. Your presentation does not match this pattern.

The Real Culprit: Severe Caloric Restriction

Consuming only 300 calories per day or nothing at all is life-threatening and directly explains your symptoms:

• Severe caloric restriction causes your body to break down muscle and fat for energy, releasing metabolic waste products that must be excreted by the kidneys 2
• This creates an obligatory water loss, leading to frequent urination with pale (dilute) urine 2
• Your chloride of 107 mmol/L (slightly elevated) reflects dehydration and electrolyte imbalance from inadequate nutrition 2
• Your ketones of 5 indicate your body is in starvation ketosis, breaking down fat for fuel because you're not eating 2

Why Pedialyte Helped

Pedialyte contains approximately 1,035 mg of sodium per liter plus other electrolytes, which temporarily corrected your electrolyte imbalances and provided your kidneys with the solutes needed to concentrate urine more effectively 1. This response actually argues against diabetes insipidus, because:

• In true diabetes insipidus, electrolyte solutions would not reduce polyuria—only desmopressin (for central DI) or specific medications (for nephrogenic DI) would help 1, 3
• Your improvement with Pedialyte indicates your kidneys can concentrate urine when given adequate electrolytes and nutrition 1

Stress, Anxiety, and Bereavement as Contributing Factors

High anxiety and stress following your relative's death are significant contributors:

• Anxiety and psychological distress can manifest with physical symptoms including altered fluid intake patterns and perceived urinary frequency 4
• Stress can affect eating behaviors and self-care, perpetuating the cycle of inadequate nutrition 4
• Being sedentary reduces your caloric needs but does not excuse consuming only 300 calories daily—this is dangerously insufficient 2

Regarding Your Chloride Question

No, Pedialyte will not "bring your chlorides down"—it will actually provide more chloride 1. Your slightly elevated chloride (107 mmol/L) reflects dehydration and metabolic stress from starvation, not chloride excess. The solution is adequate nutrition and hydration, not avoiding electrolytes.

Critical Action Plan

You need immediate intervention to prevent serious organ damage, cardiac arrhythmias, and potentially death 2:

Immediate Steps (Starting Today):

• Increase caloric intake to at least 1,200-1,500 calories per day minimum, with adequate protein (at least 0.8-1 g/kg body weight) 2
• Consume normal salt intake (4-6 g/day) through regular food 2
• Continue drinking water based on thirst, but focus on eating regular meals 1, 2
• Consider mental health evaluation for anxiety, depression, and possible disordered eating given your severe caloric restriction and recent bereavement 4

Monitoring:

• Daily weight monitoring until nutritional status normalizes 2
• Repeat serum sodium and osmolality within 7 days after resuming adequate nutrition 2
• If symptoms persist despite adequate nutrition and hydration for 2-4 weeks, then formal evaluation for diabetes insipidus would be appropriate 2

About Your 24-Hour Urine Collection

Complete the collection as planned, but understand that the results will likely reflect your current state of severe malnutrition and dehydration, not diabetes insipidus 1, 5. For accurate interpretation:

• Maintain your usual fluid intake based on thirst during collection 1
• Collect ALL urine over exactly 24 hours, starting by emptying your bladder completely and discarding that urine, then collecting everything thereafter 1
• The completeness of collection is paramount—any missed urine invalidates the test 1

Common Pitfalls to Avoid

• Do not assume diabetes insipidus based on polyuria alone—many conditions cause frequent urination, and your labs don't support this diagnosis 1, 5
• Do not continue severe caloric restriction—this is causing immediate harm and will lead to serious complications 2
• Do not ignore the psychological component—grief, anxiety, and possible disordered eating require professional attention 4
• Your eGFR of 99 mL/min/1.73m² is normal, indicating your kidneys are functioning well despite the metabolic stress you're placing on them 1

The most urgent issue is not diabetes insipidus—it is your dangerously inadequate caloric intake and the need for mental health support following your bereavement. Address these first, and your urinary symptoms will likely resolve.