The proportion of overweight people is increasing continuously, especially in the so-called affluent society. This is an expression of the social development of the society in which the supply of food is steadily increasing and the physical activity is decreasing. With increasing technical progress, heavy work has almost completely disappeared from the world of work. The diverse health consequences of obesity have a negative impact on life expectancy and lead to a significant increase in health care costs. The treatment of obesity is one of the greatest challenges in medicine. Prevention is the most important pillar in the fight against obesity. Information and education are far from being sufficient. Rather, we need role models that invite to more movement and no ideals of beauty that the average citizen admires but with whom he hardly identifies.

Body Mass Index (BMI) and overweight
BMI = body weight [kg]/ (height [m])
The BMI is used in practice to assess the extent of overweight and to calculate the cardiovascular risk.

BMI 18-25 kg/m2 normal weight
BMI 25-30 kg/m2 overweight
BMI 30-35 kg/m2 obesity grade I
BMI 35-40 kg/m2 obesity grade II
BMI >40 kg/m2 obesity grade III

Effects of overweight and obesity
In the first place the classic trias
– Arterial hypertension
– Dyslipidemia
– Type II diabetes mellitus
With subsequent arteriosclerotic complications from calcification of the vessels, which lead to an increased risk of suffering a stroke, a heart attack and other circulatory disorders.
Furthermore
– Increased cancer risk, especially for colon cancer
– Fast wear of the joints
– Infertility
– Psychological problems due to stigmatization
– Development of disturbed eating behavior

Causes and risks for the development of overweight and obesity
Genetic causes come first. The simple reason is that we still have genes from the time when it was important for an individual’s survival to gain weight quickly when food was available and to lose weight slowly during periods of hunger. Accordingly, our genes were adapted in the course of evolution. Now there are practically no hunger periods in our regions.
Furthermore:
– Lack of physical exercise
– Hormonal causes (e.g. thyroid disorders, polycystic ovarian syndrome)
– Metabolic diseases
– Medications (e.g. antidepressants, steroids)
– Stress
– Eating disorders
– Night work, shift working and lack of sleep
– Low socio-economic status

Therapy of overweight and obesity
The treatment of overweight and obesity is one of the most difficult tasks in medicine. The most important thing is that the patient wants to lose weight himself and has not been persuaded to do so. A lasting therapeutic success requires a lifelong change of lifestyle. If the patient has been persuaded to the therapy but does not want to do it himself, failure is inevitable. There is a large market for overweight treatments. It guarantees to the providers a secure income because the patients use to come back again and again. Reducing the weight is much easier than keeping the lower weight afterwards. Most diets are more harmful than useful because they are one-sided and lead to the so-called yo-yo effect. The alternating decrease and increase of weight are more harmful to health in the long term then being overweight. Therapy depends on the degree of overweight or obesity. With a BMI between 25 and 30 and the absence of other risk factors, there is no need to intervention, since scientific studies have shown that this group of people has the highest life expectancy. In the presence of high blood pressure, high blood lipid levels or diabetes, it is advisable to reduce the weight gently. From a BMI of 30, structured programs of exercise and nutritional advice are the therapy of choice. Movement is the most important part of therapy. For a training effect, you should be physically active at least 3 times a week. The greatest effect is obtained by an activity of 30 minutes 5 times a week. You don’t need necessarily achieve top performance in a gym. Everyday physical activity is much more important: fast walking instead of taking the car, taking the stairs instead of taking the elevator, carrying the groceries, doing housework. With sufficient and regular physical activity, it is almost unimportant what you eat, but only how high the calorie intake is. The total number of calorie and the fat content should be reduced. The best diet is the mediterranean diet because it is a healthy, all-nutrient diet. The taste experience is high and you don’t need to suffer hunger which is very important for the success of the treatment. If the BMI is >35, the presence of eating disorders should be checked and, if necessary, treated with psychotherapy. Cooperation between different disciplines is necessary. From BMI of 40 or a lower BMI but several failed conservative therapy attempts, surgical measures are possible. We roughly differentiate between two groups of interventions, both of which can be made minimally invasively using the so-called keyhole procedure. With the restrictive procedures such as the gastric band, the stomach volume is reduced, which leads to a faster feeling of satiety and thus less food intake. In addition, there are procedures that on the one hand reduce the stomach volume and at the time reduce food absorption. They include partial gastric resection and gastric bypass. It applies to all patients that they have to implement a lifelong change in their habits. As a rule, overweight patients require lifelong specialist care.