|Obesity & Serotonin|
|It is increasingly recognized that obesity is not a failure of will or behaviour, nor is it a disorder of body weight regulation. It is a chronic medical condition, like hypertension or diabetes.In the obese person, body weight is just as carefully regulated as it is in non obese persons, but regulation is around an elevated set point. This homeostatic set point — strongly influenced by genetics and is probably controlled by neurotransmitters that signal hunger or signal satiety.Only those individuals with exceptional will power and the ability to tolerate discomfort are able to defeat this homeostatic mechanism through dietary energy restriction.|
|If eating behaviour, like mood and personality, is simply the result of a mixture of neurotransmitters, then a pharmaceutical intervention may be more effective than attempts at behaviour modification, just as antidepressants are generally more effective for clinical depression than a psychiatrist.At one time, amphetamines were being used for weight control, although when the drug was discontinued, the patient gained back all the lost weight. However, if obesity is a chronic medical condition in the same way that hypertension is a chronic medical condition, then weight gain following drug discontinuation is no different from rising blood pressure after the discontinuation of antihypertensive medications.|
|Using serotonin reuptake inhibitors for weight lossIn the early 1980s, clinical investigators discovered a link between serotonin and eating disorders. The discovery was unexpected: during clinical trials of the serotonin reuptake-inhibitor fluoxetine, one side effect noted was weight loss. Even before this, seotonin was implicated in the eating disorders.
The dietary starch is converted to sugar, sugar stimulates the pancreas to release insulin, insulin raises brain levels of the amino acid tryptophan, tryptophan is a precursor of serotonin, and serotonin regulates mood, producing a sense of well-being. Therefore, obese people load up on carbohydrates to elevate mood. In studies with obese women, it was found that a high-carbohydrate snacks improved mood.
Subsequent studies showed that serotoninergics helped overeaters lose weight. One agent — dexfenfluramine — was particularly effective for cutting food intake. Dexfenfluramine is the active portion of the anti-obesity agent fenfluramine. Its side effects are dry mouth, diarrrhea, unsteadiness, and memory problems along with cardiac problems..
Because of the seriousness of the valvular heart disease associated with the use of fenfluramine, the medication was withdrawn from the market in September of 1997
According to the National Institutes of Health and the Centers for Disease Control, more than 30% of Americans are 20% or more overweight, and one third of women and more than one quarter of men are trying to lose weight at any given time.