Obesity: considerations about etiology, metabolism, and the use of experimental models

Abstract

Studies have been conducted in order to identify the main factors that contribute to the development of obesity. The role of genetics has also been extensively studied. However, the substantial augmentation of obesity prevalence in the last 20 years cannot be justified only by genetic alterations that, theoretically, would have occurred in such a short time. Thus, the difference in obesity prevalence in various population groups is also related to environmental factors, especially diet and the reduction of physical activity. These aspects, interacting or not with genetic factors, could explain the excess of body fat in large proportions worldwide. This article will focus on positive energy balance, high-fat diet, alteration in appetite control hormones, insulin resistance, amino acids metabolism, and the limitation of the experimental models to address this complex issue.

Keywords:

• obesity
• diet
• leptin
• fat
• ghrelin
• experimental models

Acknowledgments

The authors are very grateful to Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) for supporting this research (Project FAPESP 96/08618-6).

Disclosure

The authors report no conflicts of interest in this work.