Order Leptin Blood Test from JustLabs for $30. Price includes lab processing at Quest Diagnostics. A one-time $18 collection fee applies per order. No insurance required.

Leptin Blood Test

Leptin

Leptin is the "satiety hormone" produced by fat cells that signals fullness to the brain. Testing helps identify leptin resistance, a condition linked to obesity and metabolic dysfunction.

Leptin is a hormone produced primarily by adipose (fat) tissue. Its main function is to signal to your brain that you have enough energy stored and don't need to eat more—essentially turning off hunger. The more fat tissue you have, the more leptin you produce.

Paradoxically, most obese individuals have high leptin levels, not low. This is because they develop "leptin resistance"—the brain stops responding to leptin's signals despite high levels. This creates a vicious cycle: the brain thinks it's starving even when fat stores are abundant, driving continued overeating and reduced metabolism.

Testing leptin levels can help identify leptin resistance and provide insights into metabolic dysfunction that standard tests may miss.

Price

$30

Results

3-5 business days

Lab Network

Quest

Fasting

8+ hrs

What's Measured

Leptin

What This Test Measures

This test measures the concentration of leptin hormone in your blood, reported in ng/mL. Levels correlate strongly with body fat percentage and are typically higher in women than men.

Who Should Consider This Test

People struggling with weight loss despite diet and exercise, those investigating persistent hunger or overeating, individuals with obesity or metabolic syndrome, anyone interested in metabolic health optimization, and people with unexplained weight gain.

Health Insights

Conditions Screened

Leptin resistanceObesity evaluationMetabolic syndromeHypothalamic dysfunctionRare leptin deficiencyWeight regulation disorders

Related Symptoms

Constant hunger despite adequate eatingDifficulty losing weightWeight gain or obesityLow energy and metabolismCravings for high-calorie foodsFeeling coldFatigue

When to Get Tested

8-hour fast required. Test in the morning for most consistent results. Leptin levels naturally fluctuate throughout the day and can be affected by recent meals.

Fasting Required

This test requires fasting for accurate results. Please follow these instructions:

  • Do not eat or drink anything except water for 8-12 hours before your blood draw.
  • Water is allowed and encouraged - stay hydrated!
  • Schedule your lab visit in the morning for convenience.
  • Continue taking any prescribed medications unless advised otherwise by your doctor.

Understanding Your Results

Normal ranges vary by sex and body composition. Men: 0.5-12 ng/mL, Women: 3.7-11.1 ng/mL. Elevated levels in obese individuals suggest leptin resistance. Very low levels are rare but may indicate leptin deficiency.

What to Expect

After placing your order, you'll receive an email from Rupa Health (our lab order partner) within 24 business hours to sign a consent form and schedule your blood draw at a Quest Diagnostics location.

The blood draw typically takes just a few minutes. Results are usually available within 3-5 business days and will appear in your secure Justlabs dashboard.

Our results include reference ranges and easy-to-understand indicators showing whether your values are within normal limits.

Frequently Asked Questions

$30

Typical hospital cash price: $150–$250

+ $28 in standard lab & physician fees at checkout (no additional bills later)

$18 lab collection + $10 physician order

Results in 3-5 business days
Fasting required (8+ hours)

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