Share this page:
Formal name: Leptin
Related tests: Lipid Profile, Thyroid Panel, Glucose, A1c, Insulin, Ghrelin

At a Glance

Why Get Tested?

To determine if you have a leptin deficiency that is contributing to obesity; to identify increased leptin; on a research basis to help understand leptin's roles in the body and its ties to obesity

When to Get Tested?

When a child has severe obesity that may be due to a very rare inherited leptin deficiency; sometimes to help evaluate obesity; when participating in a research study

Sample Required?

A blood sample drawn from a vein in your arm

Test Preparation Needed?


The Test Sample

What is being tested?

Leptin is an adipokine, a hormone produced primarily by fat cells (adipocytes) and to a lesser degree by other tissues, including the placenta in pregnant women. This test measures the amount of leptin in the blood.

Leptin is a hormone that helps regulate appetite by signaling hunger satisfaction (satiety) to receptors in the hypothalamus in the brain; when sufficient food has been consumed, it tells the body that it is no longer hungry. In a normal feedback response, a low level of leptin triggers hunger and an increase in food consumption. As the level of leptin rises from an increase in fat cells, hunger diminishes and food consumption drops off.

Insufficient leptin can cause persistent hunger as the body attempts to protect itself from perceived underfeeding (starvation). Very rare inherited leptin deficiencies can cause severe obesity through constant hunger and constant eating that starts in early childhood. Leptin replacement therapy has been shown to be successful in treating some of those affected.

Obesity is most commonly associated with elevated leptin levels. This is thought to be due to a resistance to leptin that is similar to the insulin resistance often seen with obesity. People who are affected are resistant to the action of leptin—they continue to experience hunger even after consuming sufficient food. The body continues to produce more leptin in an attempt to compensate and in response to the perceived hunger. However, about 10% of those who are obese are estimated to have some degree of leptin deficiency.

There is significant interest in better understanding leptin's ties to obesity. Obesity is a major health concern in the U.S. because it increases the risk of many conditions, such as high blood pressure (hypertension), dyslipidemias (high cholesterol and/or high triglycerides), type 2 diabetes, joint problems, sleep apnea, coronary heart disease, stroke, and some cancers. The rate of obesity has increased steadily over the last 20 years in all age ranges and, according to the Centers for Disease Control and Prevention, more than one-third of adults and 17% of children and teens in this country are currently classified as obese. Classification is based on body mass index or BMI. (See Common Questions #2).

A recent study found that in some people a leptin level might be more accurate than the traditional body mass index in gauging how much excess fat a person is carrying. In general, the higher the level of leptin in the bloodstream, the more fat tissue a person has. In the study, this was especially true with older women and in those with large muscles or dense bones where the results of the BMI score could be misleading.

Research is ongoing to evaluate leptin's roles in the body and the links between leptin and obesity, and between leptin and successful weight loss. There is also continued interest in determining whether a leptin-based treatment might be useful for those who are obese and leptin-deficient.

How is the sample collected for testing?

A blood sample is obtained by inserting a needle into a vein in the arm.

NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.

Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.

Is any test preparation needed to ensure the quality of the sample?

No test preparation is needed.

The Test

Common Questions

Ask a Laboratory Scientist

This form enables you to ask specific questions about your tests. Your questions will be answered by a laboratory scientist as part of a voluntary service provided by one of our partners, American Society for Clinical Laboratory Science. If your questions are not related to your lab tests, please submit them via our Contact Us form. Thank you.

* indicates a required field

Please indicate whether you are a   

You must provide a valid email address in order to receive a response.

| Read The Disclaimer

Spam Prevention Equation

| |

Article Sources

« Return to Related Pages

NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used.

Hamdy, O. (Updated 2013 January 24). Obesity. Medscape Reference [On-line information]. Available online at http://emedicine.medscape.com/article/123702-overview#showall through http://emedicine.medscape.com. Accessed February 2013.

(© 1995-2013). Leptin. Mayo Clinic Mayo Medical Laboratories [On-line information]. Available online at http://www.mayomedicallaboratories.com/test-catalog/Overview/91339 through http://www.mayomedicallaboratories.com. Accessed February 2013.

Miehle, K. et. al. (2012). Leptin, Adiponectin and Other Adipokines in Gestational Diabetes Mellitus and Pre-eclampsia. Medscape from Clin Endocrinol. 2012;76(1):2-11 [On-line information]. Available online at http://www.medscape.com/viewarticle/755467 through http://www.medscape.com. Accessed February 2013.

Lawson, E. (2012). Leptin Levels are Associated With Decreased Depressive Symptoms in Women Across the Weight Spectrum, Independent of Body Fat. Medscape from Clin Endocrinol. 2012;76(4):520-525 [On-line information]. Available online at http://www.medscape.com/viewarticle/760937 through http://www.medscape.com. Accessed February 2013.

Schwarz, S. and Windle, M. (Updated 2012 December 12). Obesity in Children. Medscape Reference [On-line information]. Available online at http://emedicine.medscape.com/article/985333-overview through http://emedicine.medscape.com. Accessed February 2013.

Chawla, J. and Youngsook P. (Updated 2012 October 3). Endocrine System Anatomy. Medscape Reference [On-line information]. Available online at http://emedicine.medscape.com/article/1948709-overview#showall through http://emedicine.medscape.com. Accessed February 2013.

Ahima, R. (2008 July 1). Revisiting leptin's role in obesity and weight loss. J Clin Invest. V 118 (7):2380–2383. [On-line information]. Available online at http://www.jci.org/articles/view/36284 through http://www.jci.org. Accessed February 2013.

Koh, K. et. al. (2008). Contemporary Reviews in Cardiovascular Medicine, Leptin and Cardiovascular Disease, Response to Therapeutic Interventions [On-line information]. Circulation v 117: 3238-3249. [On-line information]. Available online at http://circ.ahajournals.org/content/117/25/3238.full through http://circ.ahajournals.org. Accessed February 2013.

Ahmet Ursavas, A. et. al. (2010 July – September). Ghrelin, leptin, adiponectin, and resistin levels in sleep apnea syndrome: Role of obesity. Ann Thorac Med. 2010 Jul-Sep; 5(3): 161–165 [On-line information]. Available online at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2930655/ through http://www.ncbi.nlm.nih.gov. Accessed February 2013.

Scheer, F. (2009 March 17). Adverse metabolic and cardiovascular consequences of circadian misalignment. PNAS v 106 (11) 4453-4458 [On-line information]. Available online at http://www.pnas.org/content/106/11/4453.long through http://www.pnas.org. Accessed February 2013.

Carlson, J. et. al. (2009 August 11). Pre- and post- prandial appetite hormone levels in normal weight and severely obese women. Nutrition & Metabolism v 6 (32) [On-line information]. Available online at http://www.nutritionandmetabolism.com/content/6/1/32 through http://www.nutritionandmetabolism.com. Accessed February 2013.

Farooqi, S. and O'Rahilly, S. (2006 December 1). Genetics of Obesity in Humans. Endocrine Reviews v 27 (7) 710-718. [On-line information]. Available online at http://edrv.endojournals.org/content/27/7/710.full through http://edrv.endojournals.org. Accessed February 2013.

Franks, P. et. al. (2007 May). Physical activity energy expenditure may mediate the relationship between plasma leptin levels and worsening insulin resistance independently of adiposity. Journal of Applied Physiology c 102 (5) 1921-1926. [On-line information]. Available online at http://jap.physiology.org/content/102/5/1921.full through http://jap.physiology.org. Accessed February 2013.

Stella L. Volpe, S. et. al. (2008 April). Effect of Diet and Exercise on Body Composition, Energy Intake and Leptin Levels in Overweight Women and Men. J Am Coll Nutr v 27 (2) 195-208 [On-line information]. Available online at http://www.jacn.org/content/27/2/195.full through http://www.jacn.org. Accessed February 2013.

Chiesa, C. et. al. (2008) Ghrelin, Leptin, IGF-1, IGFBP-3, and Insulin Concentrations at Birth: Is There a Relationship with Fetal Growth and Neonatal Anthropometry? Clinical Chemistry v 54 (3) 550–558 [On-line information]. Available online at http://www.clinchem.org/content/54/3/550.full through http://www.clinchem.org. Accessed February 2013.

Henson, M. and Castracane, V. (2006 February 1). Leptin in Pregnancy: An Update. Biology of Reproduction v 74 (2) 218-229 [On-line information]. Available online at http://www.biolreprod.org/content/74/2/218.full through http://www.biolreprod.org. Accessed February 2013.

S17 Choquet, H. and Meyre, D. (2011 May) Genetics of Obesity: What have we Learned? Curr Genomics v 12(3): 169–179. [On-line information]. Available online at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3137002/ through http://www.ncbi.nlm.nih.gov. Accessed February 2013.

Considine, R, et al. Serum Immunoreactive-Leptin Concentrations in Normal-Weight and Obese Humans. N Engl J Med 1996; 334:292-295. Available online at http://www.nejm.org/doi/full/10.1056/NEJM199602013340503#t=articleTop through http://www.nejm.org. Accessed February 2013.

Nirav R. Shah, Eric R. Braverman. Measuring Adiposity in Patients: The Utility of Body Mass Index (BMI), Percent Body Fat, and Leptin. PLoS One. Published April 2, 2012. Available online at http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0033308 through http://www.plosone.org. Accessed February 2013.