Promising New Causal Explanations for Obesity and Obesity-Related Diseases

Abstract

Current explanations for obesity center around a predisposition in genotype and phenotype, possibly triggered by an inflammatory process or event, and exacerbated by environmental and psychological factors. It is likely that a variety of physiologic factors may act in combination to produce clinical obesity. Leptin resistance may be an important neurochemical cause of obesity; elevated leptin levels have been correlated with weight gain over extended time periods. Genetic studies support the postulate that a gene originating with our cave-dwelling ancestors, critical to survival when food was scare, has evolved into a trigger for obesity and related diseases. A variety of biochemical markers are prevalent in obesity and obesity-linked disease states. C-reactive protein, interleukin-6, and others are elevated in obesity, supporting the hypothesis that inflammation plays a role in the condition. Tumor necrosis factor-α is overexpressed in obesity and diabetes, suggesting that it may be part of the link between the 2 conditions.