Chronic rapidly increasing obesity has become a major public health problem in industrialized countries. The World Health Organization (WHO) has called obesity epidemic first non-infectious history. Its management is seen as a priority, and even more so than being overweight affects individuals of younger and younger.
Data collected by WHO showed that nearly half of Americans are overweight, while a quarter of the population is frankly obese, a figure that may reach 70% of some populations. Europe is not spared, with 30% of adults overweight, obesity affecting 12% of adults in Western Europe. In France, the prevalence of obesity has increased by about 45% between l987 and 1996, and the number of obese individuals is estimated at 8 million. Obesity also affects the young population, since the number of obese children has doubled since the 80s, and the prevalence of obesity is estimated at 10-12% in children aged 6 to 12 years. Some studies predict that at this rate half the European population is affected by obesity by 2030.
Obesity is a condition characterized by excess body fat (or fat). An international standard has been adopted for measuring overweight and obesity. This is the Body Mass Index (BMI), defined as weight divided by the square of height in kg/m2 (see box). BMI estimates the degree of obesity and thus allows to assess the health risk (co-morbidity) associated with it (see box). A person is considered obese when this value is greater than or equal to 30 kg/m2. In addition to BMI, it should also measure the distribution of body fat. Indeed, it is now accepted that the presence of excess fat in the abdomen causes an increased risk to health. Thus, a waist circumference exceeding 88 cm in women, and 102 cm in men, indicating visceral obesity and increased risk of developing other clinical problems.
The reasons for the development of obesity are many. Obesity is a multifactorial symptom resulting from complex interactions between a genetic and more or less conducive environment in which it operates. Indeed, the heritability of fatness is undeniable. Certain subjects resist obesity whilst others are particularly sensitive to changes in diet and its fat content. For example, an overweight child with at least one obese parent has a 80% risk of becoming obese as adults, against only 10% chance if both parents were poor.
The various family analysis concluded that there was a small number of genes playing a role in body size and regional distribution of body fat. The results of research of the past three years suggest the involvement of a score of different genes or chromosomal regions. This means that the biochemical and physiological systems responsible for the formation of obesity are multiple and occur at different stages of energy regulation. The human genome and advances in molecular genetics should therefore allow to classify the “obesity” based on the metabolic mechanisms put into play.
However, research suggests that genetic factors are involved themselves in less than one third of cases of obesity, showing that heredity does not explain everything. Furthermore, it is unlikely that the human genome has changed in the space of one generation to the point of causing the obesity epidemic raging. The fact that, globally, overweight affects more people than the current generation of parents and grandparents, shows that other factors are to blame. Indeed, the rapid changes of environment and behavior in recent decades are major determinants of the rapid development of this disease. And it is primarily in dietary habits and lifestyle that are the root causes of the obesity epidemic.
Eating foods with high calories and high in fat, coupled with a lifestyle more sedentary plays a role in the development of overweight and obesity trends around. Remember that gaining weight is never the result of an imbalance of energy balance, that is to say between calorie intake and food use by the organization (to operate and maintain body temperature ). When food intake exceeds energy expenditure, excess energy is stored as body fat. If this mechanism is set aside has enabled man to overcome periods of scarcity, it seems to serve in times of glut.
Far from being merely a matter of aesthetics, being overweight causes many health complications: respiratory disorders, hypertension, cardiovascular disease, metabolic disorders (diabetes type 2, noninsulin-dependent diabetes says bold), rheumatic problems, increased risk of certain cancers. Other disorders such as cholesterol, sleep apnea, osteoarthritis, infertility, venous insufficiency, reflux esophagitis is frequently associated with obesity. In the United States for example, overweight is responsible for the increase in diabetes among people in their thirties, in the space of ten years, this disease has increased 76% in this age group and 33% in the general population. Among children, too, a form of ultra-early diabetes type 2 appeared a few years ago, which is growing alarmingly. The first cases of atypical diabetes have been detected in France in 1999 and the new disease is spreading.
The treatment of obesity does not limit itself to solve a weight problem, but is to take charge of the medical problem in its entirety. These treatment and prevention of physical disorders while developing a program tailored to weight loss. Recall that the approach of drug treatment of obesity is controversial. Medications such as diuretics, anorexigenic catabolic and promote weight loss but do not act specifically on the reduction of fatty tissue. In addition, generally effective in early treatment, they have not proven long term. And in many cases, they are the cause of severe metabolic disturbances, and therefore strongly discouraged. Thus, diuretics that force the kidneys to excrete more water can cause serious electrolyte imbalance, or dehydration. The catabolic can be toxic, causing side effects on the heart and central nervous system. The anorectic can lead to addiction and other psychological disorders they were removed from the European market at the beginning of the year.
A new treatment acting on the gastrointestinal tract to block fat absorption in part by the agency was recently prescribed. Other molecules are under development or after marketing procedure. Finally, in some cases, the severity of obesity is such that surgery on the stomach is stimulated, the gastroplasty. It aims to reduce food intake by reducing gastric volume: the stomach and divided into two compartments, like an hourglass, the narrow passage is created using a ring. Considering its effect on weight loss and reduction of associated pathologies, it seems that the effectiveness of gastroplasty in the short and medium terms is recognized. But among experts, Some wonder about the soundness of a surgical measure in response to a behavioral problem.
However, medication does not solve the problems of weight and not “cure” not obese. They must be medically monitored, and enroll in a comprehensive, involving diet and regular physical activity. It is now commonly accepted that the diet must be customized, that is to say into consideration the habits and feeding behavior of each individual, but also realistic, since it is imperative that they are long-term.
In industrialized countries, the economic cost of obesity and associated diseases is 2.4 to 5% of health spending. Of course, the numbers vary depending on the disease taken into account in assessing the costs and the proportion of cases attributable to obesity-related illnesses each. Thus, a recent U.S. study estimated $ 238 billion (253 billion euros) the expenditure incurred in the United States to treat diseases related to obesity such as diabetes and cardiovascular disease, these data do not take include expenditures related to treatment of obesity itself. In Canada, the direct cost attributable to obesity treatment has been estimated at more than 1.8 billion Canadian dollars in 1997 (1.3 billion euros), while in France the cost was $ 11.9 million francs in 1992 (1.8 million).
The treatment of obesity is so complicated that it is better not to accumulate excess weight rather than trying to lose. It is therefore important to adopt preventive measures to avoid the occurrence of overweight among children and the installation of obesity in adults. The only way not to gain weight is to limit energy intake and exercise physical activity, prevention campaigns should focus on the acquisition of basic knowledge about nutrition and proper eating habits while encouraging regular exercise. This is to establish a healthy lifestyle, and not to develop obsessive behavior for weight control. It should perhaps be guided by the preventive methods developed in Finland, the only country to have stabilized their numbers.