The problems of overweight and obesity

Historically, a moderate degree of overweight was considered desirable. In a society in which food was scarce, fatness demonstrated greater than average wealth and prosperity. 

This attitude persists in many developing countries today food is scarce, and few people have enough to eat, let alone too much. 

The psychological and social problems of the obese spill over to people of normal weight as well. There is continual advertising pressure for slimness , and newspapers and magazines are full of propaganda for slimness and diets for weight reduction. This may be one of the factors in the development of major eating disorders such as anorexia nervosa and bulimia (section 8.3.1.1). 

Obesity, and especially abdominal obesity (section 6.2.3), is strongly associated with insulin resistance and the development of non-insulin-dependent diabetes mellitus (section 10.7). This is largely the result of increased circulating concentrations of non-esterified fatty acids (released from plasma lipoproteins by lipoprotein lipase section 5.5.6.2). Non-esterified fatty acids decrease muscle uptake and utilization of glucose and may also antagonize insulin action. Weight loss results in a considerable improvement in glycaemic control in patients with early non-insulin-dependent diabetes. 

In addition to the diseases caused by, or associated with, obesity, obese people are considerably more at risk of death during surgery and post-operative complications. There are three main reasons for this  

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