If you believe that there is no excuse for somebody putting on excessive weight and that an obese person simply eats too much and takes too little exercise, then think again. Overeating and not taking enough exercise can certainly result in obesity, but these are not the only causes of obesity.
It is widely agreed that, in addition to the problems of overeating and taking insufficient exercise, there is a whole range of obesity causes. For example, in some individuals there is believed to a genetic factor which can pre-dispose them to obesity. Some forms of the genes responsible for controlling appetite and metabolism for example are thought to lead to obesity when they are found in combination with certain environmental conditions.
Additionally, there are various genetic disorders which can produce obesity. For example, Prader-Willi syndrome, first described in 1956 and named after Andrea Prader and Heinrich Willi, is a genetic disorder in which sufferers have an insatiable appetite and accumulate excessive fat, particularly in the central region of the body.
Illness can also produce weight gain and obesity. Certainly not the only, but perhaps the best know illness which frequently leads to obesity is hypothyroidism. Although the illness itself normally produces only mild weight gain, when combined with the right environmental conditions, this can quickly develop into a substantial increase in weight.
Medication is another cause of weight gain. There are numerous medications which can produce weight gain, but one class of drugs which is a cause of particular concern and has attracted the attention of the Food and Drug Administration (FDA) is the new class of atypical antipsychotics which can have a significant effect on the metabolism.
Certain diets can also produce obesity without the individual concerned realizing what is happening. This is not a simple case of overeating, but of eating the wrong type of food. For example, in some people certain foods will produce unusually high levels of blood sugar immediately after eating.
There are also some specific eating disorders which can cause obesity, such as binge eating disorder. A psychiatric disorder (and an element of bulimia nervosa), binge eating disorder is a condition in which sufferers cannot control their eating and often intersperse binge eating into an otherwise normal eating habit.
Surprisingly enough, dieting can also lead to obesity. Most diets fail and we are seeing more and more people who spend a significant portion of their lives moving from one diet to the next in the hope of losing weight. Invariably they lose weight while they are on a diet but then put it back on again, along with a little bit extra, every time they come off a diet. As they try a variety of different diets their weight cycles up and down, but the underlying trend is for their weight to gradually increase, often resulting in obesity.
These are just a few of the causes of obesity, other than simply eating too much and not taking enough exercise, and, in many cases, individuals have little or no control of their situation.