Appetite control: why we fail to stop eating even when we are full?

Abstract

We often eat more than our body needs. We live in an environment where high calorie food is abundant and physical activities are limited. Living in this environment, maintaining healthy bodyweight becomes challenging and obesity becomes a social burden. Why do we continue to eat even after the metabolic needs are satisfied? Feeding is an ancient behavior essential to survive. Thus the mechanisms to regulate appetite, energy expenditure, and energy storage are well conserved throughout animals. Based on this conservation, we study why we fail to control appetite using a simple genetic model system C. elegans. We have discovered certain genetic components that when misregulated have animals eat more and store more fat. In this review we discuss how these genes work in the appetite control circuit to ultimately understand overall appetite control behavior. We will also briefly discuss how social influence affects feeding regardless of the metabolic status of an animal.

Keywords

cGMP / TGFβ / C. elegans / satiety / appetite / obesity

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Acknowledgements

This work is supported by Virginia Commonwealth University.

Compliance with ethics guidelines

Kristen Davis and Young-Jai You declare that they have no conflict of interest. This article does not contain any studies with human or animal subjects performed by any of the authors.

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg