Leptin · low result
What does a low Leptin mean?
Short answer
Low leptin reflects low body fat — athletes, lean individuals, people who have lost significant weight, and those with eating disorders — and tells the brain to conserve energy and raise appetite. Very low leptin is one reason periods stop in low-weight women and why weight regain after dieting is common. Congenital leptin deficiency is extremely rare.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
What is the normal range for Leptin?
- Male, age 18+: 0.500 – 12.5 ng/mL
- Female, age 18+: 4.70 – 24.0 ng/mL
Full reference table, citations and testing options: Leptin biomarker page.
What are the common causes of low Leptin?
- Low body fat, recent significant weight loss, intensive training
- Anorexia nervosa, malnutrition, fasting
- Lipodystrophy (rare)
- Congenital leptin deficiency (very rare)
What symptoms go with low Leptin?
- Increased hunger, low energy, feeling cold
- Absent or irregular periods, low libido, low bone density over time
What do clinicians usually check next?
- Assess energy availability — intake versus training
- FSH, LH, estradiol or testosterone, TSH, vitamin D
- Sports-medicine or eating-disorder specialist review if periods have stopped or weight is very low
Follow-up tests available at TestWell: TSH (Thyroid Stimulating Hormone) ($26.99), TSH + Free T4 ($27.99), FSH (Follicle Stimulating Hormone) ($29.99), LH (Luteinizing Hormone) ($36.99), Estradiol (E2) ($35.99).
How do you recheck Leptin?
Prices are cash-pay; every order adds one $6 lab processing fee. Physician authorization is included; no insurance or referral needed.
| Test or panel | Type | Price | Fasting | Results |
|---|---|---|---|---|
| Metabolism & Weight Loss Panel | Panel · 8 tests | $119.99 | Yes | 2–5 business days |
| Total Body Panel | Panel · 49 tests | $499.99 | Yes | 5–10 business days |
| Leptin | Test | $36.99 | Yes | 3–5 business days |
Common questions
Why does leptin fall with dieting?
Leptin drops faster than fat mass, which is the body's defense against starvation: hunger rises and metabolism slows. It is one reason maintenance is harder than the diet itself.
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.