July 2017


Obesity is defined as an excessive accumulation of fat. Numerous studies have shown the involvement of certain genes in the occurrence of overweightness and obesity. They may indeed play a role in the predisposition to obesity by influencing one's feeding behavior, hormone production, as well as the function of certain proteins and metabolism. Modification or abnormality of these genes is never the sole cause of weight gain or obesity, and eating habits as well as education both take a major part in its appearance and aggravation. Obesity is increasing in industrialized countries, affecting nearly 30% of Americans, 12% of French; children are increasingly affected. Obesity increases the risk of some dangerous diseases such as cardiovascular disease. Contrary to what one might think, obesity is more common in children from disadvantaged socio-economic backgrounds. This is a major public health issue because of its impact on physical and psychological health.


The main symptom of obesity is an increase in fat body mass. The definition is based on a calculation called BMI "Body Mass Index", which corresponds to dividing the weight in kilograms by height squared in meters. Apart from this overweightness, obesity is not responsible for visible signs, but for many complications including:
  • cardiac complications with increased risk of atherosclerotic arteries which become clogged, hypertension, thromboembolic disease, heart failure and specific complications of these diseases;
  • Difficulty breathing, ultimately progressing to respiratory failure;
  • sleep apnea;
  • an increased risk of developing diabetes;
  • Increased susceptibility to osteoarthritis;
  • A greater risk of developing cancer...

Several other diseases are concerned by this disorder.


Diagnosis to determine the type of obesity is based on BMI:
  • 25 to 30: overweight;
  • 30 to 35: moderate obesity;
  • 35 to 40: severe obesity;
  • over 40: morbidly obese.

These values are determined in adults and children, and there are curves to identify normal values of BMI by sex and age. Measuring waist circumference is also possible for adults to differentiate male obesity, called android obesity, where there is a predominance of fat deposition in the upper body (abdomen in particular), whereas in women fat is deposited in the buttocks and thighs. Abdominal obesity may cause various complications.


The treatment of obesity is based on:
  • nutritional education;
  • the practice of a sport or other physical activity;
  • psychological support.

In extreme cases, this may require bariatric surgery, including the placement of a gastric band.


The hereditary factor predisposes certain individuals to obesity. However, the genetic transmission of obesity is not fully demonstrated. The familial transmission of a nutritional lifestyle is clearly implicated in the occurrence of obesity. The correcting of abnormal eating habits started at an early prevents all forms of obesity. A balanced diet, coupled with regular physical activity or a sport, prevents obesity in most cases. Similarly, psychological support is necessary for a person who is not strong mentally and who may therefore turn to food. Prevention also relies on an early screening of overweightness, hence the need to regularly check one's BMI.


Original article published by . Translated by Jeff. Latest update on November 5, 2013 at 10:47 AM by Jeff.
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