Obesity and Appetite Hormones in Humans: an Overview


Obesity is one of the most important public health problems in the world. It is a medical condition with a chronic imbalance between energy intake and energy expenditure. The prevalence of overweight and obesity in adults and children are rapidly rising, and several factors contributing the increased risk of developing obesity are inactivity, overeating, age, give up smoking, ethnicity, secondary obesity and inherited predisposition or genetic defects.

The regulation of appetite involves highly complex peripheral and central systems that are processed in the brain. The appetite hormones (hypothalamic orexigenic neuropeptides) play critical roles in the control of food intake and obesity. Understanding the pharmacology and physiology of appetite regulation and investigation of the role of appetite hormones in the regulation of food intake in humans will allow us to find potential therapeutic targets for the treatment of obesity.

Key Concepts:

  • Obesity is a medical condition, with excessed body weight in the form of fat, resulted from the failure of energy homoeostasis.

  • Many factors cause obesity including inactivity, overeating, higher age, drugs, diseases, ethnicity and inherited predisposition to obesity or specific genetic defects.

  • Obesity is most prevalent in worldwide, WHO predicted that they would rise up to 2.3 billion overweight and 700 million obese in 2015.

  • Obesity predisposes some chronic diseases as type 2 diabetes, cardiovascular diseases and various cancers or shortens life duration and increases mortality rates.

  • Neural and humoral signals regulate appetite in brain. The appetite hormones control food intake and energy expenditure, whereas a chronic imbalance in those hormones causes obesity.

Keywords: obesity; appetite; neuropeptide Y; agouti and agouti‐related peptide; galanin and galanin‐like peptide; ghrelin; melanin‐concentrating hormone; endocannabinoids; orexins


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Web Links

IASO/IOTF (2010) Obesity the global epidemic. http://www.iaso.org/iotf/obesity/obesitytheglobalepidemic/

WHO (2006) Factsheet 311 September. http://www.who.int/mediacentre/factsheets/fs311/en/index.html

WHO (2007) WHO statement: Controlling the global obesity epidemic. http://www.who.int/nutrition/topics/obesity/en/

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Caylak, Emrah(Jun 2012) Obesity and Appetite Hormones in Humans: an Overview. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0024163]